- Email: [email protected]
Realisation of all photonic logic gates using plasmonic-based photonic structure through bandgap analysis
Optik - International Journal for Light and Electron Optics 194 (2019) 163123
Contents lists available at ScienceDirect
Optik journal homepage: www.elsevier.com/locate/ijleo
Original research article
Realisation of all photonic logic gates using plasmonic-based photonic structure through bandgap analysis
T
⁎
I.S. Amiria,b, G. Palaic, , S.K. Tripathyd, S.R. Nayake a
Computational Optics Research Group, Advanced Institute of Materials Science, Ton Duc Thang University, Ho Chi Minh City, Viet Nam Faculty of Applied Sciences, Ton Duc Thang University, Ho Chi Minh City, Viet Nam Department of Electronics and Communication Engineering, Gandhi Institute for Technological Advancement (GITA), Bhubnaeswar, India d Department of Electronics and Communication Engineering, National Institute of Technology, Silchar, Assam, India e Department of Computer Science and Engineering, Chitkara University Institute of Engineering and Technology, Chitkara University, India b c
A R T IC LE I N F O
ABS TRA CT
Keywords: Triangular photonic structure Photonic logic gates Photonic bandgap
NOT, AND, OR, Ex-OR, NAND, NOR,and Ex-NOR logic gates have been realized in this work with the help of plasmonic-based two-dimensional triangular structure. The physics of the research manipulates with the photonic band gap analysis where the mathematics of the band calculation manipulates with plane wave expansion. Further both physics and mathematics of this communication relies on effective refractive index,the diameter of air holes and lattice constant of the structure to envisage optical logic gates. Moreover, the operation ofphotonic logic interacts with two signal of input (orange and red signals) where IR signal of 1.2 μm is taken as a power supply signal. Lastly, the output of this paper discloses that the suitable combination of plasmonic-based triangular structures with suitable values of lattice constant and diameter of air holes bestows all type of logic gates, which could be future applications in the field of optical computing.
1. Introduction The research on the optical computer has been focusing throughout the globe since a couple of decades because of its several advantages as compared to its counter field of an electronic one. The intrinsic mechanism for benefits of optical computer agrees with high speed, high bandwidth and carrying capacity and overall efficiency where photon particles play a vital role which has superior properties as compared to the nature of electrons inan electronic computer. Moreover, the overall efficiency of the optical computer depends on each element or components of the same computer. Out of which the component called optical logic gates play a vital role at the time of operation of optical computation. These logic gates enhance the speed of computation on the entire system, which is needed by our society and modern technology now.Again focusing on the physics of the optical system, it deals with non-linear materials which are exhibiting many hi-tech applications as compared to linear material. Though many research deals with nonlinear material but few of them focus on optical logic gates pertaining to theoretical demonstration [1–5]. Again focusing on optical logic gates, reference [1] designs the various type of logic gates,which states that logic gates are possible without amplifiers and they propose nano semiconductor materials for the same. Similarly, reference [2] proposes logic gate application could be possible with the help of nanowire, where some of the logic gates have been established in reference [3] through small air holes of the photonic crystal structure. Further reference [4] builds the universal logic gates with the help of a photonic crystal structure. Moreover, reference [5] realizes the different type of gates using a grating structure.Nevertheless above said works focuses on optical logic gates,
⁎
Corresponding author. E-mail addresses: [email protected] (I.S. Amiri), [email protected] (G. Palai).
https://doi.org/10.1016/j.ijleo.2019.163123 Received 29 April 2019; Accepted 18 July 2019 0030-4026/ © 2019 Elsevier GmbH. All rights reserved.
Optik - International Journal for Light and Electron Optics 194 (2019) 163123
I.S. Amiri, et al.
Fig. 1. Schematic diagram of the plasmonic-based triangular structure.
the present communication establishes all type of logic gates with the help of triangular structure through photonic band gap analysis, which is not found in the literature. The present communication is divided in the following section as follows; Section 2 discusses the proposed triangular structure through which logic gate operation is made. Similarly, the principle of logic gate operations is analyzed in Section 3. Further result and is presentationis discussed in Section 4. Further, the conclusions are indicated in Section 5.
2. Proposed triangular photonic structure The proposed structure in this work deal with the two-dimensional plasmonic-based triangular crystal where six numbers of air holes have been etched on it in a regular manner. The same figure is shown in Fig. 1; In this figure copper based plasmonic material is considered as background material and six numbers of air holes have been made on it. The lattice constant and diameter of air holes of the same plays key role for logic gate application Moreover these two parameters virtually controls the operation of said logic gate pertaining to (0,0), (0,1), (1,0) and (1,1). Furthermore, the physics of the aforementioned operation manipulates with the effective refractive indices of background material, which is clearly discussed in the following section.
3. Principle of logic operation The principle of logic operation deals with the intrinsic mechanism of the structure and we classified into two categories such as intrinsic and external mechanism. The internal mechanism interacts with the generation of the input signal with the help of said phonic structures where external mechanism manipulates with the operational computation of logic gates.
3.1. Internal mechanism In this work, there are two types of signals such as orange and red signals have been chosen to realize the generation of input signals. The triangular structure which is considered here for generating all inputs shown in Fig. 2(a) Fig. 2(a) indicates the generation of input signals corresponding to the orange and red signals, which is represented as signal-1 and signal-2 respectively.Further to generate four input combination of orange and red signals; we deal with an apt structure parameter of lattice constant and diameter of air holes. For examples; the present structure disallows both the signals at certain values of lattice constant and diameter of air holes, which is considered as the input of (0, 0).Similarly, the other input parameters of (0,1), (1,0) and (1,1) can be realized by choosing the rightpermutation of (lattice constant of the structure, diameter of air holes).For the illustration of same, we can analyze as following;(0,1) is understood by the disallowing of orange (signal-1) and allowing of red (signal-2) signals. Similarly (1,0) is realized by allowing the signal-1 and forbids the signal-2. Moreover (1,1) input is envisaged by considering the allowing of both the signals. The outcomes of the above structure (0,0), (0,1),(1,0) and (1,1) can be the input of the proposed logic gate operation which is clearly discussed in the following section. 2
Optik - International Journal for Light and Electron Optics 194 (2019) 163123
I.S. Amiri, et al.
Fig. 2. (a): Aschematic representation of a 2D triangular structure for showing the input generation. (b): the entire mechanism of logic gate operation using the 2D triangular photonic crystal structure.
3.2. External mechanism The external mechanism of logic gate operation deals with an operational principle of entire logic gate operation which gives either 0 or 1. To comprehend the same, let us concentrate on the following diagram (Fig. 2(b)). Fig. 2(b) represents the mechanism of the proposed logic gate operation with the help of a photonic crystal structure. Form this figure, it is understood that the operation is divided into two parts such as the generation of input signals other will be delivering the output. An output end a signal of IR is applied, which is a counterpart of the supply signal of an electronic logic gate. Though the present paper discloses all type of logic gate operation, let us discuss AND gate thoroughly as follows; Here the input section generates a signal of (0,0), (0,1),(1,0) and (1,1) and incidents to the output structure. First a signal of (0,0) along with IR signal of 1.2 μm incident to a structure so that the output structure is designed in an appropriate manner that it disallows to all signals which represent output as ‘0′. It indicates (0,0) inputs gives as ‘0′ output. Secondly, a signal of (0,1) along with power supply signal to the structure, the structure is designed in an appropriate way that it disallows to all signals which represent output as ‘0′. It indicates (0,1) inputs gives as ‘0′ output. Similarly, a signal of (1,0) along with IR signal incident to a structure so that the output structure is proposed in such manner that it disallows to all signals which represent output as ‘0’. It indicates (1,0) inputs gives as ‘0’ output. Lastly a signal of (1,1) along with IR signal of 1.2 μm incident to a structure so that the output structure is designed 3
Optik - International Journal for Light and Electron Optics 194 (2019) 163123
I.S. Amiri, et al.
Fig. 3. (a): Dispersion diagram of a 2D plasmonic-based triangular photonic structure for lattice constant of 750 nm and diameter of air holes of 735 nm. (b): Dispersion diagram of 2D plasmonic-based triangular photonic structure for lattice constant of 650 nm and diameter of air holes of 632 nm. (c): Dispersion diagram of 2D plasmonic-based triangular photonic structure for lattice constant of 430 nm and diameter of air holes of 387 nm. (d): Dispersion diagram of 2D plasmonic-based triangular photonic crystal structure for lattice constant of 750 nm and diameter of air holes of 230 nm.
in such way that it allows to all signals which represent output as ‘1’. It indicates (1,1) inputs gives as ‘1’ output. The above representation is the implicationof AND gate operation. Further,the other logic gate operation such as NOT,OR,NAND,NOR,Ex-OR and Ex-NOR have been investigated with the help of similar principle. 4. Result and interpretation From Fig. 2(b), it is observed that the entire logic gate operation depends on two sections such as input and output end. The input sections are onus for the generation of (0,0), (1,0), (0,1) and (1,1), where output end is responsible to generate 0 or 1 signal. All input and output signals have been realized using plasmonic-based onthe proposed photonicstructures via photonic bandgap analysis which is deployedwith the help of plane-wave expansion technique [6]. To do so, we choose specific values of the lattice constant of the structure and diameter of air holes along with the effective refractive index of background material. For example Fig. 3(a)–(d) is represented as (0,0), (1,0), (0,1) and (1,1) respectively, From Fig. 3, it is realized that normalized frequency and propagation constant (wave vector) is taken along perpendicular and parallel axis respectively. Since the present contribution deals with orange and red signals, we focus on the same regime of wavelength only. Basically, the variation of signal pertaining to orange to red is from 570 nm to 740 nm. Moreover, the principle of the generation of the signals lies with allows and/or disallow of the signals, which could be clearly visible from Fig. 3. Further, the numerical value of the wavelength of the signals corresponding to each diagram is computed as follows; In these diagrams; the vertical axis is represented as normalized frequency (a/λ), which is the ratio of lattice constant and wavelength of the signal.Moreover knowing the values of the normalized parameter of the band (either allowed or forbidden), the numerical value of the wavelength corresponding to the same band is obtained. Again with the help of same principle Fig. 3(a) signifies that a signal of 558 nm to 920 nm is completely forbidden, which implies that both orange and red signals are getting completely reflected from the proposed structure with having lattice constantand diameter of air holes of 750 nm and 735 nm respectively,that indicates that (0,0) signals of the input. Similarly Fig. 3(b)–(d) signifies as (1,0), (0.1) and (1,1) respectively as orange signal is allowed and red signal is disallowed in Fig. 3(b), orange signal is disallowed and red signal is allowed in Fig. 3(c) and both signals of orange and red signals are allowed in Fig. 3(d). The details of the lattice parameter and diameter of air holes corresponding above four combinations of the signal are mentioned in Table 1. After the generation of the signals of inputs, we move to deal with the generation of output signals as follows; Further, we employed a plane-wave expansion technique to calculate the band gap of the proposed structure in similar to Fig. 3. Nevertheless,the present communication executes the gate operation for all logic gates; let us make a brief realization on AND gate only. From Fig. 2, it is understood that a power supply signal of 1200 nm (IR signal) is considered at the output end to obtain output result of either 0 or 1. The output result is mentioning in Fig. 4(a)–(d) corresponding to the input of (0,0), (0,1), (1,0) and (1,1) 4
Optik - International Journal for Light and Electron Optics 194 (2019) 163123
I.S. Amiri, et al.
Table 1 The entire simulation outcomes for the understanding of input and output signals. INPUT Category of Input Signal
Lattice Spacing (a) in nm
Diameter of holes (d) in nm
(0,0) (0,1) (1,0) (1,1)
750 650 430 750
735 632 387 230
OUTPUT Category of “GATE “Operation
Lattice Spacing (a) in nm
Diameter of holes (d) in nm
NOT AND OR NAND NOR Ex-OR Ex-NOR
615 710 750 685 650 740 700
500 640 360 480 400 590 300
Fig. 4. (a): Dispersion diagram of a 2D plasmonic-based triangular photonic structure for lattice constant710 nm and diameter of air holes of 640 nm for showing output 0 with respect to input (0,0). (b): Dispersion diagram of 2D plasmonic-based triangular crystal structure for lattice constant of 710 nm and diameter of air holes of 640 nm for showing output 0 with respect to input (0,1). (c): Dispersion diagram of 2D plasmonicbased triangular photonic structure for lattice constant of 710 nm and diameter of air holes of 640 nm for showing output 0 with respect to input (1,0). (d): Dispersion diagram of 2D plasmonic-based triangular photonic structure for lattice constantof 710 nm and diameter of air holes of 640 nm for showing output s1 with respect to input (1,1).
respectively. The numerical parameters and the principle of computation of the wavelength in Fig. 4 are same as figure Moreover the universal principle of AND gate operation deals with ‘0′ as output if either input is zero, where the output would be ‘1′ if both inputs are 1. To envisage the same, the physics of computation relies on both effective refractive indices [7] of the substrate material, lattice constant of the structure and diameter of holes to realize the AND operation. Realizing the same, it is an interestingly to declare that the four operations of AND gate are made at single structure only corresponding to the lattice constantof 710 nm and diameter of holes of 640 nm. Moreover, the signal of IR would always transmit through the structure which is mentioning through the green in color in all 5
Optik - International Journal for Light and Electron Optics 194 (2019) 163123
I.S. Amiri, et al.
diagrams of Fig. 4. This IR signal is equivalent to the power supply in an electronic logic gate operation.Furthermore using the same principle, the different logic gate operation can be made at specific values of lattice constantand diameter of holes. Though the full simulation result for other logic gate operation of NOT, OR, NAND, NOR, Ex-OR and Ex-NOR have not been disclosed here, the entire outcomes of the same are placed in tabular form in Table 1; Fig. 1 shows the values of lattice constantof the structure and diameter of holes for generation input and output signals corresponding to NOT, AND, OR, NAND, NOR, Ex-OR and Ex-NOR gate operation. From the above table, it is envisaged that the lattice constantof the structure and diameter of holes differ from different logic gates; for example, the values of lattice constantand diameter for OR gate is not same with Ex-OR or with other gates. 5. Conclusion The intact logic gate operation using plasmonic-based photonic crystal structure pertaining to orange and red signals is minutely described in this communication. The principle of optical logic gate operation interacts with the generation of both input and output signals. Finally, it is stated that both diameter of etched holes and lattice constant along with the effective refractive indices with respect to the orange and red signal of plasmonic-based photonic structure play key role to design logic gates in the photonic computer system. References [1] P. Singh, D.K. Tripathi, S. Jaiswal, H.K. Dixit, All-optical logic gates: designs, classification, and comparison, Adv. Opt. Technol. (2014) 1–13, https://doi.org/10. 1155/2014/275083 Article ID 275083. [2] Bob Yirka, Using nanowires to build all-optical logic gates, Phys.org (Report) (July 30) (2018), https://phys.org/news/2018-07-nanowires-all-optical-logic-gates. html. [3] V. Jandieri, R. Khomeriki, D. Erni, Realization of true all-optical AND logic gate based on nonlinear coupled air-hole type photonic crystal waveguides, Opt. Express 26 (16) (2018) 19845–19853. [4] P.M. Barreto, Vitaly F.R. Esquerre, Optical Logic Gates; Latin America Optics and Photonics Conference; OSA Technical Digest (Optical Society of America, paper Th3A.2 (2018) https://doi.org/10.1364/LAOP.2018.Th3A.2. [5] G. Palai, Monika Tripathy, Rasmita Das, P. KissanSubudhi, Realization of all logic gates using hybrid grating structure: an application of silicon photonics, Optik 147 (October) (2017) 256–262. [6] G. Palai, S.K. Tripathy, T. Sahu, A novel technique to measure the sucrose concentration in hydrogel sucrose solution using two dimensional photonic crystal structures, Optik 125 (January (1)) (2014) 349–352. [7] J. Parsons, A. Polman, A copper negative index metamaterial in the visible / near-infrared, Appl. Phys. Lett. 99 (2011) 161108.
6
Contents lists available at ScienceDirect
Optik journal homepage: www.elsevier.com/locate/ijleo
Original research article
Realisation of all photonic logic gates using plasmonic-based photonic structure through bandgap analysis
T
⁎
I.S. Amiria,b, G. Palaic, , S.K. Tripathyd, S.R. Nayake a
Computational Optics Research Group, Advanced Institute of Materials Science, Ton Duc Thang University, Ho Chi Minh City, Viet Nam Faculty of Applied Sciences, Ton Duc Thang University, Ho Chi Minh City, Viet Nam Department of Electronics and Communication Engineering, Gandhi Institute for Technological Advancement (GITA), Bhubnaeswar, India d Department of Electronics and Communication Engineering, National Institute of Technology, Silchar, Assam, India e Department of Computer Science and Engineering, Chitkara University Institute of Engineering and Technology, Chitkara University, India b c
A R T IC LE I N F O
ABS TRA CT
Keywords: Triangular photonic structure Photonic logic gates Photonic bandgap
NOT, AND, OR, Ex-OR, NAND, NOR,and Ex-NOR logic gates have been realized in this work with the help of plasmonic-based two-dimensional triangular structure. The physics of the research manipulates with the photonic band gap analysis where the mathematics of the band calculation manipulates with plane wave expansion. Further both physics and mathematics of this communication relies on effective refractive index,the diameter of air holes and lattice constant of the structure to envisage optical logic gates. Moreover, the operation ofphotonic logic interacts with two signal of input (orange and red signals) where IR signal of 1.2 μm is taken as a power supply signal. Lastly, the output of this paper discloses that the suitable combination of plasmonic-based triangular structures with suitable values of lattice constant and diameter of air holes bestows all type of logic gates, which could be future applications in the field of optical computing.
1. Introduction The research on the optical computer has been focusing throughout the globe since a couple of decades because of its several advantages as compared to its counter field of an electronic one. The intrinsic mechanism for benefits of optical computer agrees with high speed, high bandwidth and carrying capacity and overall efficiency where photon particles play a vital role which has superior properties as compared to the nature of electrons inan electronic computer. Moreover, the overall efficiency of the optical computer depends on each element or components of the same computer. Out of which the component called optical logic gates play a vital role at the time of operation of optical computation. These logic gates enhance the speed of computation on the entire system, which is needed by our society and modern technology now.Again focusing on the physics of the optical system, it deals with non-linear materials which are exhibiting many hi-tech applications as compared to linear material. Though many research deals with nonlinear material but few of them focus on optical logic gates pertaining to theoretical demonstration [1–5]. Again focusing on optical logic gates, reference [1] designs the various type of logic gates,which states that logic gates are possible without amplifiers and they propose nano semiconductor materials for the same. Similarly, reference [2] proposes logic gate application could be possible with the help of nanowire, where some of the logic gates have been established in reference [3] through small air holes of the photonic crystal structure. Further reference [4] builds the universal logic gates with the help of a photonic crystal structure. Moreover, reference [5] realizes the different type of gates using a grating structure.Nevertheless above said works focuses on optical logic gates,
⁎
Corresponding author. E-mail addresses: [email protected] (I.S. Amiri), [email protected] (G. Palai).
https://doi.org/10.1016/j.ijleo.2019.163123 Received 29 April 2019; Accepted 18 July 2019 0030-4026/ © 2019 Elsevier GmbH. All rights reserved.
Optik - International Journal for Light and Electron Optics 194 (2019) 163123
I.S. Amiri, et al.
Fig. 1. Schematic diagram of the plasmonic-based triangular structure.
the present communication establishes all type of logic gates with the help of triangular structure through photonic band gap analysis, which is not found in the literature. The present communication is divided in the following section as follows; Section 2 discusses the proposed triangular structure through which logic gate operation is made. Similarly, the principle of logic gate operations is analyzed in Section 3. Further result and is presentationis discussed in Section 4. Further, the conclusions are indicated in Section 5.
2. Proposed triangular photonic structure The proposed structure in this work deal with the two-dimensional plasmonic-based triangular crystal where six numbers of air holes have been etched on it in a regular manner. The same figure is shown in Fig. 1; In this figure copper based plasmonic material is considered as background material and six numbers of air holes have been made on it. The lattice constant and diameter of air holes of the same plays key role for logic gate application Moreover these two parameters virtually controls the operation of said logic gate pertaining to (0,0), (0,1), (1,0) and (1,1). Furthermore, the physics of the aforementioned operation manipulates with the effective refractive indices of background material, which is clearly discussed in the following section.
3. Principle of logic operation The principle of logic operation deals with the intrinsic mechanism of the structure and we classified into two categories such as intrinsic and external mechanism. The internal mechanism interacts with the generation of the input signal with the help of said phonic structures where external mechanism manipulates with the operational computation of logic gates.
3.1. Internal mechanism In this work, there are two types of signals such as orange and red signals have been chosen to realize the generation of input signals. The triangular structure which is considered here for generating all inputs shown in Fig. 2(a) Fig. 2(a) indicates the generation of input signals corresponding to the orange and red signals, which is represented as signal-1 and signal-2 respectively.Further to generate four input combination of orange and red signals; we deal with an apt structure parameter of lattice constant and diameter of air holes. For examples; the present structure disallows both the signals at certain values of lattice constant and diameter of air holes, which is considered as the input of (0, 0).Similarly, the other input parameters of (0,1), (1,0) and (1,1) can be realized by choosing the rightpermutation of (lattice constant of the structure, diameter of air holes).For the illustration of same, we can analyze as following;(0,1) is understood by the disallowing of orange (signal-1) and allowing of red (signal-2) signals. Similarly (1,0) is realized by allowing the signal-1 and forbids the signal-2. Moreover (1,1) input is envisaged by considering the allowing of both the signals. The outcomes of the above structure (0,0), (0,1),(1,0) and (1,1) can be the input of the proposed logic gate operation which is clearly discussed in the following section. 2
Optik - International Journal for Light and Electron Optics 194 (2019) 163123
I.S. Amiri, et al.
Fig. 2. (a): Aschematic representation of a 2D triangular structure for showing the input generation. (b): the entire mechanism of logic gate operation using the 2D triangular photonic crystal structure.
3.2. External mechanism The external mechanism of logic gate operation deals with an operational principle of entire logic gate operation which gives either 0 or 1. To comprehend the same, let us concentrate on the following diagram (Fig. 2(b)). Fig. 2(b) represents the mechanism of the proposed logic gate operation with the help of a photonic crystal structure. Form this figure, it is understood that the operation is divided into two parts such as the generation of input signals other will be delivering the output. An output end a signal of IR is applied, which is a counterpart of the supply signal of an electronic logic gate. Though the present paper discloses all type of logic gate operation, let us discuss AND gate thoroughly as follows; Here the input section generates a signal of (0,0), (0,1),(1,0) and (1,1) and incidents to the output structure. First a signal of (0,0) along with IR signal of 1.2 μm incident to a structure so that the output structure is designed in an appropriate manner that it disallows to all signals which represent output as ‘0′. It indicates (0,0) inputs gives as ‘0′ output. Secondly, a signal of (0,1) along with power supply signal to the structure, the structure is designed in an appropriate way that it disallows to all signals which represent output as ‘0′. It indicates (0,1) inputs gives as ‘0′ output. Similarly, a signal of (1,0) along with IR signal incident to a structure so that the output structure is proposed in such manner that it disallows to all signals which represent output as ‘0’. It indicates (1,0) inputs gives as ‘0’ output. Lastly a signal of (1,1) along with IR signal of 1.2 μm incident to a structure so that the output structure is designed 3
Optik - International Journal for Light and Electron Optics 194 (2019) 163123
I.S. Amiri, et al.
Fig. 3. (a): Dispersion diagram of a 2D plasmonic-based triangular photonic structure for lattice constant of 750 nm and diameter of air holes of 735 nm. (b): Dispersion diagram of 2D plasmonic-based triangular photonic structure for lattice constant of 650 nm and diameter of air holes of 632 nm. (c): Dispersion diagram of 2D plasmonic-based triangular photonic structure for lattice constant of 430 nm and diameter of air holes of 387 nm. (d): Dispersion diagram of 2D plasmonic-based triangular photonic crystal structure for lattice constant of 750 nm and diameter of air holes of 230 nm.
in such way that it allows to all signals which represent output as ‘1’. It indicates (1,1) inputs gives as ‘1’ output. The above representation is the implicationof AND gate operation. Further,the other logic gate operation such as NOT,OR,NAND,NOR,Ex-OR and Ex-NOR have been investigated with the help of similar principle. 4. Result and interpretation From Fig. 2(b), it is observed that the entire logic gate operation depends on two sections such as input and output end. The input sections are onus for the generation of (0,0), (1,0), (0,1) and (1,1), where output end is responsible to generate 0 or 1 signal. All input and output signals have been realized using plasmonic-based onthe proposed photonicstructures via photonic bandgap analysis which is deployedwith the help of plane-wave expansion technique [6]. To do so, we choose specific values of the lattice constant of the structure and diameter of air holes along with the effective refractive index of background material. For example Fig. 3(a)–(d) is represented as (0,0), (1,0), (0,1) and (1,1) respectively, From Fig. 3, it is realized that normalized frequency and propagation constant (wave vector) is taken along perpendicular and parallel axis respectively. Since the present contribution deals with orange and red signals, we focus on the same regime of wavelength only. Basically, the variation of signal pertaining to orange to red is from 570 nm to 740 nm. Moreover, the principle of the generation of the signals lies with allows and/or disallow of the signals, which could be clearly visible from Fig. 3. Further, the numerical value of the wavelength of the signals corresponding to each diagram is computed as follows; In these diagrams; the vertical axis is represented as normalized frequency (a/λ), which is the ratio of lattice constant and wavelength of the signal.Moreover knowing the values of the normalized parameter of the band (either allowed or forbidden), the numerical value of the wavelength corresponding to the same band is obtained. Again with the help of same principle Fig. 3(a) signifies that a signal of 558 nm to 920 nm is completely forbidden, which implies that both orange and red signals are getting completely reflected from the proposed structure with having lattice constantand diameter of air holes of 750 nm and 735 nm respectively,that indicates that (0,0) signals of the input. Similarly Fig. 3(b)–(d) signifies as (1,0), (0.1) and (1,1) respectively as orange signal is allowed and red signal is disallowed in Fig. 3(b), orange signal is disallowed and red signal is allowed in Fig. 3(c) and both signals of orange and red signals are allowed in Fig. 3(d). The details of the lattice parameter and diameter of air holes corresponding above four combinations of the signal are mentioned in Table 1. After the generation of the signals of inputs, we move to deal with the generation of output signals as follows; Further, we employed a plane-wave expansion technique to calculate the band gap of the proposed structure in similar to Fig. 3. Nevertheless,the present communication executes the gate operation for all logic gates; let us make a brief realization on AND gate only. From Fig. 2, it is understood that a power supply signal of 1200 nm (IR signal) is considered at the output end to obtain output result of either 0 or 1. The output result is mentioning in Fig. 4(a)–(d) corresponding to the input of (0,0), (0,1), (1,0) and (1,1) 4
Optik - International Journal for Light and Electron Optics 194 (2019) 163123
I.S. Amiri, et al.
Table 1 The entire simulation outcomes for the understanding of input and output signals. INPUT Category of Input Signal
Lattice Spacing (a) in nm
Diameter of holes (d) in nm
(0,0) (0,1) (1,0) (1,1)
750 650 430 750
735 632 387 230
OUTPUT Category of “GATE “Operation
Lattice Spacing (a) in nm
Diameter of holes (d) in nm
NOT AND OR NAND NOR Ex-OR Ex-NOR
615 710 750 685 650 740 700
500 640 360 480 400 590 300
Fig. 4. (a): Dispersion diagram of a 2D plasmonic-based triangular photonic structure for lattice constant710 nm and diameter of air holes of 640 nm for showing output 0 with respect to input (0,0). (b): Dispersion diagram of 2D plasmonic-based triangular crystal structure for lattice constant of 710 nm and diameter of air holes of 640 nm for showing output 0 with respect to input (0,1). (c): Dispersion diagram of 2D plasmonicbased triangular photonic structure for lattice constant of 710 nm and diameter of air holes of 640 nm for showing output 0 with respect to input (1,0). (d): Dispersion diagram of 2D plasmonic-based triangular photonic structure for lattice constantof 710 nm and diameter of air holes of 640 nm for showing output s1 with respect to input (1,1).
respectively. The numerical parameters and the principle of computation of the wavelength in Fig. 4 are same as figure Moreover the universal principle of AND gate operation deals with ‘0′ as output if either input is zero, where the output would be ‘1′ if both inputs are 1. To envisage the same, the physics of computation relies on both effective refractive indices [7] of the substrate material, lattice constant of the structure and diameter of holes to realize the AND operation. Realizing the same, it is an interestingly to declare that the four operations of AND gate are made at single structure only corresponding to the lattice constantof 710 nm and diameter of holes of 640 nm. Moreover, the signal of IR would always transmit through the structure which is mentioning through the green in color in all 5
Optik - International Journal for Light and Electron Optics 194 (2019) 163123
I.S. Amiri, et al.
diagrams of Fig. 4. This IR signal is equivalent to the power supply in an electronic logic gate operation.Furthermore using the same principle, the different logic gate operation can be made at specific values of lattice constantand diameter of holes. Though the full simulation result for other logic gate operation of NOT, OR, NAND, NOR, Ex-OR and Ex-NOR have not been disclosed here, the entire outcomes of the same are placed in tabular form in Table 1; Fig. 1 shows the values of lattice constantof the structure and diameter of holes for generation input and output signals corresponding to NOT, AND, OR, NAND, NOR, Ex-OR and Ex-NOR gate operation. From the above table, it is envisaged that the lattice constantof the structure and diameter of holes differ from different logic gates; for example, the values of lattice constantand diameter for OR gate is not same with Ex-OR or with other gates. 5. Conclusion The intact logic gate operation using plasmonic-based photonic crystal structure pertaining to orange and red signals is minutely described in this communication. The principle of optical logic gate operation interacts with the generation of both input and output signals. Finally, it is stated that both diameter of etched holes and lattice constant along with the effective refractive indices with respect to the orange and red signal of plasmonic-based photonic structure play key role to design logic gates in the photonic computer system. References [1] P. Singh, D.K. Tripathi, S. Jaiswal, H.K. Dixit, All-optical logic gates: designs, classification, and comparison, Adv. Opt. Technol. (2014) 1–13, https://doi.org/10. 1155/2014/275083 Article ID 275083. [2] Bob Yirka, Using nanowires to build all-optical logic gates, Phys.org (Report) (July 30) (2018), https://phys.org/news/2018-07-nanowires-all-optical-logic-gates. html. [3] V. Jandieri, R. Khomeriki, D. Erni, Realization of true all-optical AND logic gate based on nonlinear coupled air-hole type photonic crystal waveguides, Opt. Express 26 (16) (2018) 19845–19853. [4] P.M. Barreto, Vitaly F.R. Esquerre, Optical Logic Gates; Latin America Optics and Photonics Conference; OSA Technical Digest (Optical Society of America, paper Th3A.2 (2018) https://doi.org/10.1364/LAOP.2018.Th3A.2. [5] G. Palai, Monika Tripathy, Rasmita Das, P. KissanSubudhi, Realization of all logic gates using hybrid grating structure: an application of silicon photonics, Optik 147 (October) (2017) 256–262. [6] G. Palai, S.K. Tripathy, T. Sahu, A novel technique to measure the sucrose concentration in hydrogel sucrose solution using two dimensional photonic crystal structures, Optik 125 (January (1)) (2014) 349–352. [7] J. Parsons, A. Polman, A copper negative index metamaterial in the visible / near-infrared, Appl. Phys. Lett. 99 (2011) 161108.
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