- Email: [email protected]
Study of transport and magnetic properties of electron-doped superconducting cuprates Eu1.85Ce0.15Cu1-yZnyO4+α-δ
Physica C: Superconductivity and its applications 557 (2019) 41–43
Contents lists available at ScienceDirect
Physica C: Superconductivity and its applications journal homepage: www.elsevier.com/locate/physc
Study of transport and magnetic properties of electron-doped superconducting cuprates Eu1.85Ce0.15Cu1-yZnyO4+α-δ
T
Risdiana , M. Manawan, L. Safriani, T. Saragi, W.A. Somantri, A. Aprilia, N. Syakir, S. Hidayat, A. Bahtiar, Fitrilawati, R.E. Siregar ⁎
Department of Physics, Padjadjaran University, Jl. Raya Bandung-Sumedang km.21 Jatinangor, Sumedang 45363, Indonesia
ARTICLE INFO
ABSTRACT
Keywords: Electron-doped superconducting cuprate Zn-substitution effect Resistivity Susceptibility
Transport and magnetic properties of electron-doped superconducting cuprates Eu1.85Ce0.15Cu1-yZnyO4+α-δ (ECCZO) with y = 0, 0.01, 0.02 and 0.05 have been studied from electrical resistivity and magnetic susceptibility measurements, in order to elucidate the effect of partially Zn-substitution for Cu to its superconductivity and localization of electron in normal state. It has been found that the onset of the critical temperature (Tc) from electrical resistivity and magnetic susceptibility measurements was observed at 13 K for y = 0 and δ values of 0.095. With increasing Zn concentration, the onset of Tc disappeared, indicating the destruction of superconductivity properties by Zn. Moreover, 0.01 of Zn substitution for Cu decreased radius of localization of electron (r) in normal state at low temperatures that may related to the evident of stripe-pinning effects by Zn in electron-doped system of ECCZO. Analysis of magnetic susceptibility data in normal state found a Zn-induced local moments in electron-doped high-Tc superconducting cuprates of ECCZO as observed in hole-doped cuprates.
1. Introduction Electron-doped superconducting cuprate has been one of interesting materials to be studied in order to elucidate mechanism of superconductivity in high Tc superconducting cuprates (HTSC). There are two types HTSC, namely, hole- and electron-doped cuprates. Comparison of some physical properties in both types has attracted research interest to clarify the origin of superconductivity. For holedoped cuprates, some papers reported various physical properties including the study of magnetism, electrical and structure properties [1–7]. However, the number of publications for electron-doped superconducting cuprates is still limited due to the difficulty in preparing the samples. For instance, superconductivity and magnetic properties in electron-doped cuprates strongly depend not only on charge carrier but also on the amount of removal of excess oxygen [8–15]. The study of relationship between magnetism and superconductivity from the effects of impurities on the Cu-spin dynamics was also intensively studied in hole- and electron-doped cuprates. In holedoped cuprates, it was found that nonmagnetic impurities of Zn suppressed superconducting volume fraction more markedly than by magnetic impurity of Ni [5,16]. Substitution of Zn to Cu in this system also tended to induce the slowing down of the Cu-spin fluctuations in
⁎
the entire superconducting regime, attributed to the pinning and stabilization of the dynamically fluctuating stripes [4,17,18]. The strong pinning of Zn in hole-doped cuprates can be described using the stripe model [19,20]. Contrastively, the Zn-induced slowing down of Cu-spin fluctuations was not observed in the electron-doped system of Pr1-xLaCexCu1-yZnyO4 from μSR experiments [9]. One of possible reasons is the effect of Pr3+ moments on the μSR spectra may be stronger than that of a small amount of Zn impurities. Therefore, to make it clearly understood, it is important to study another system of electrondoped cuprates without Pr3+ moments [9]. In this paper, we reported the temperature dependence of electrical resistivity and magnetic susceptibility of electron-doped cuprates Eu1.85Ce0.15Cu1-yZnyO4+α-δ (ECCZO) with y = 0–0.05, in order to investigate effect of Zn substitution to its superconductivity and localization of electron that may related to the stripe-pinning effect. 2. Experimental Polycrystalline samples of ECCZO with y = 0, 0.01, 0.02, and 0.05 were prepared by the ordinary solid-state reaction method [9,13]. Annealing in flowing Ar gas at various temperatures in a range of 900 °C–950 °C for 10 h–15 h was performed in order to remove the
Corresponding author. E-mail address: [email protected] (Risdiana).
https://doi.org/10.1016/j.physc.2018.12.007 Received 12 October 2016; Received in revised form 17 December 2018; Accepted 26 December 2018 Available online 27 December 2018 0921-4534/ © 2018 Elsevier B.V. All rights reserved.
Physica C: Superconductivity and its applications 557 (2019) 41–43
Risdiana et al.
Fig 1. Temperature dependence on normalized electrical resistivity of ρ/ρ300K (a), (1/T)1/4 versus ln ρ (b) and (c) Zn concentration (y) dependence on radius of localization (r) of electron for Eu1.85Ce0.15Cu1-yZnyO4+α-δ with y = 0, 0.01, 0.02, 0.05 and various δ values.
doped and electron-doped cuprates [4,9]. The transport properties in non superconducting state can be studied by calculating the effect of Zn concentration to its radius of localization of electron (r) using variable range hopping mechanism as expressed in Eq. (1).
(T ) =
0 exp
T0 T
1 4
,
(1)
where ρ0 and T0 are resistivity and temperature characteristic in the ground state. T0 can be equal to 1/r3 where r is radius of localization of electron. Fig. 1(b) shows temperature dependence on resistivity plotted as (1/ T)1/4 versus ln ρ for ECCZO at low temperatures in between 13 and 30 K. Solid lines indicating the best-fit results was obtained using Eq. (1). Fig. 1(c) shows Zn concentration (y) dependence on r extracted from Fig 1(b). The value of r started to decrease significantly when Cu was substituted by 0.01 of Zn. This result may related to the stripe pinning by Zn as observed in hole-doped cuprates [4,17,18]. This result also has good agreement with the evident of charge ordering in electron-doped cuprates [23] that was pinned by 0.01 of Zn. With increasing y to 0.02, the value of r increases and then almost constant when the value of y was changed from 0.02 to 0.05. It may due to the destruction of the stripe or charge ordering by large concentration of Zn as in the case of hole-doped cuprates [4,19,20]. Fig. 2 shows temperature dependence on magnetic susceptibility (χ) of ECCZO in a magnetic field of 5 Oe on field cooling. The sample with y = 0 shows bulk superconductivity with Tc∼13 K. The onset Tc from magnetic susceptibility measurement is similar with the value of Tc from electrical resistivity measurement [22]. With increasing Zn concentration, the onset of Tc disappeared. The value of magnetic susceptibility in normal state is almost temperature independent in all samples. The temperature-independent of magnetic susceptibility (χ0) was subtracted from χ. The difference in value of χ0 is quite small compared to the value of χ. In detail, plotting graphs of 1/χ against temperature in normal state at temperatures in between 13 and 30 K are displayed in the insert of Fig. 2. It is observed that the gradient of 1/χ decreases with the Zn substitution, indicating the increase in the Curie constant with the Zn substitution. That is, the present results may show Zn-induced local moments, which is consistent with the NMR data in hole-doped cuprates of YBa2(Cu1-yZny)3O6+x [17].
Fig 2. Temperature dependence on magnetic susceptibility χ of Eu1.85Ce0.15Cu1-yZnyO4+α−δ with y = 0, 0.01, 0.02, 0.05 and various δ values.
excess oxygen (α) at the so-called apical site. The value of removed oxygen (δ) was estimated from the weight change due to annealing [9,21]. All samples were checked by the powder x-ray diffraction measurements and found that the samples were in a single phase. Electrical-resistivity and DC magnetic-susceptibility measurements were carried out to know the superconducting transition temperature (Tc), transport and magnetic properties. The electrical resistivity was measured with DC current in a four-probe configuration at temperatures from 4.2 to 300 K. DC magnetic-susceptibility measurements were carried out at low temperatures down to 2 K using a standard SQUID magnetometer in a magnetic field of 5 Oe on field cooling in Graduate School of Engineering, Tohoku University, Japan. 3. Results and discussion Fig. 1(a) shows temperature dependence on normalized electrical resistivity (ρ/ρ300K) of ECCZO with y = 0, 0.01, 0.02, 0.05 and δ values of 0.095, 0.090, 0.107, 0.045. Onset of Tc was observed at about 13 K for y = 0 [22]. For ECCZO with y = 0.01, 0.02 and 0.05, temperature dependence on normalized electrical resistivity shows semiconductinglike behavior of ρ-T with no sign of onset of Tc. These results show the destruction of superconductivity properties by Zn. These phenomena were also observed in other superconducting cuprates both in hole-
4. Conclusion We prepared high quality polycrystalline samples and studied the transport and magnetic properties of electron-doped high-Tc 42
Physica C: Superconductivity and its applications 557 (2019) 41–43
Risdiana et al.
superconducting cuprates Eu1.85Ce0.15Cu1-yZnyO4 with y = 0, 0.01, 0.02, 0.05 and various δ values. Onset of Tc is observed in Eu1.85Ce0.15Cu1-yZnyO4+α−δ with y = 0 at about 13 K for δ values of 0.095. For Eu1.85Ce0.15Cu1-yZnyO4+α−δ with y = 0.01, 0.02 and 0.05, temperature dependence on electrical resistivity exhibited semiconducting-like behavior of ρ-T with no sign of Tc. It is also found that the value of r started to decrease significantly when Cu was substituted by 0.01 of Zn that may related to the stripe pinning by Zn. The onset Tc from magnetic susceptibility measurement is similar with the value of Tc from electrical resistivity measurement. With increasing Zn concentration, the onset of Tc from magnetic susceptibility also disappeared. Detail analysis of magnetic susceptibility data in normal state found a Zn-induced local moments in electron-doped high-Tc superconducting cuprates Eu1.85Ce0.15Cu1-yZnyO4+α−δ as observed in holedoped cuprates. The present results show that partially Zn subsitution for Cu in electron-doped system of Eu1.85Ce0.15Cu1-yZnyO4+α−δ not only destructed superconductivity properties but also showed the evident of stripe-pinning effects.
(1995) 561. [2] K. Yamada, C.H. Lee, K. Kurahashi, J. Wada, S. Wakimoto, S. Ueki, H. Kimura, Y. Endoh, S. Hosoya, G. Shirane, R.J. Birgeneau, M. Greven, M.A. Kastner, Y.J. Kim, Phys. Rev. B 57 (1998) 6165. [3] K. Suzuki, T. Adachi, Y. Tanabe, Y. Koike, T. Kawamata, Risdiana, T. Suzuki, I. Watanabe, Phys. Rev. B 82 (2010) 054519. [4] Risdiana, Y. Tanabe, K. Omori, T. Suzuki, I. Watanabe, A. Koda, W. Higemoto, Y. Koike, Phys. Rev. B 77 (2008) 054516. [5] T. Adachi, N. Oki, Risdiana, S. Yairi, Y. Koike, I. Watanabe, Phys. Rev. B 78 (2008) 134515. [6] Y. Koike, T. Adachi, N. Oki, Risdiana, M. Yamazaki, T. Kawamata, T. Noji, K. Kudo, N. Kobayashi, I. Watanabe, K. Nagamine, Physica C 426–431 (2005) 189. [7] L. Miu, A.M. Ionescu, I Ivan, T. Miu, T. Adachi, K. Omori, Y. Koike, Physica C 519 (2015) 79. [8] Y. Tokura, H. Takagi, S. Uchida, Nature 337 (1989) 345. [9] Risdiana, T. Adachi, N. Oki, Y. Koike, T. Suzuki, I. Watanabe, Phys. Rev. B 82 (2010) 014506. [10] N.P. Armitage, P. Fournier, R.L. Greene, Rev. Mod. Phys. 82 (2010) 2421. [11] Y. Krockenberger, H. Yamamoto, A. Tsukada, M. Mitsuhashi, M. Naito, Phys. Rev. B 85 (2012) 184502. [12] T. Adachi, Y. Mori, A. Takahashi, M. Kato, T. Nishizaki, T. Sasaki, N. Kobayashi, Y. Koike, J. Phys. Soc. Jpn. 82 (2013) 063713. [13] Risdiana, L. Safriani, W.A. Somantri, T. Saragi, T. Adachi, I. Kawasaki, I. Watanabe, Y. Koike, Adv. Mater. Res. 896 (2014) 354. [14] T.B. Charikova, N.G. Shelushinina, G.I. Harus, D.S. Petukhov, O.E. Petukhova, A.A. Ivanov, Physica C 525-526 (2016) 78. [15] M. Yamamoto, Y. Kohori, H. Fukazawa, A. Takahashi, T. Ohgi, T. Adachi, Y. Koike, J. Phys. Soc. Jpn. 85 (2016) 024708. [16] T. Adachi, N. Oki, Risdiana, S. Yairi, Y. Koike, I. Watanabe, Physica C 460–462 (2007) 1172. [17] A.V. Mahajan, H. Alloul, G. Collin, J.F. Marucco, Phys. Rev. Lett. 72 (1994) 3100. [18] C.M. Smith, A.H.C. Neto, A.V. Balatsky, Phys. Rev. Lett. 87 (2001) 177010. [19] T. Adachi, S. Yairi, Y. Koike, I. Watanabe, K. Nagamine, Phys. Rev. B 70 (2004) 060504(R). [20] T. Adachi, S. Yairi, K. Takahashi, Y. Koike, I. Watanabe, K. Nagamine, Phys. Rev. B 69 (2004) 184507. [21] M. Fujita, T. Kubo, S. Kuroshima, T. Uefuji, K. Kawashima, K. Yamada, I. Watanabe, K. Nagamine, Phys. Rev. B 67 (2003) 014514. [22] Risdiana, S. Pratiwi, D. Suhendar, W.A. Somantri, L. Safriani, T. Saragi, AIP Conf. Proc. 1712 (2016) 050020. [23] E.H. da Silva Neto, R. Comin, F. He, R. Sutarto, Y. Jiang, R.L. Greene, G.A. Sawatzky, A. Damascelli, Science 347 (2015) 282.
Acknowledgments We would like to thank Y. Koike, T. Adachi, M. Kato, T. Noji, T. Kawamata and H. Sato for their technical support in the powder x-ray diffraction, electrical-resistivity and magnetic-susceptibility measurements at Tohoku University, Japan. These works were supported by Academic Leadership Grant of Padjadjaran University. Part of this work was also supported by research grant of International Research Collaboration and Scientific Publication 2015 (No: 393/UN6.R/PL/ 2015), 2016 (No: 431/UN6.3.1/PL/2016), 2017 (No: 718/UN6.3.1/PL/ 2017), 2018 (1133/ UN6.D/LT/2018). References [1] J.M. Tranquada, B.J. Sternlieb, J.D. Axe, Y. Nakamura, S. Uchida, Nature 375
43
Contents lists available at ScienceDirect
Physica C: Superconductivity and its applications journal homepage: www.elsevier.com/locate/physc
Study of transport and magnetic properties of electron-doped superconducting cuprates Eu1.85Ce0.15Cu1-yZnyO4+α-δ
T
Risdiana , M. Manawan, L. Safriani, T. Saragi, W.A. Somantri, A. Aprilia, N. Syakir, S. Hidayat, A. Bahtiar, Fitrilawati, R.E. Siregar ⁎
Department of Physics, Padjadjaran University, Jl. Raya Bandung-Sumedang km.21 Jatinangor, Sumedang 45363, Indonesia
ARTICLE INFO
ABSTRACT
Keywords: Electron-doped superconducting cuprate Zn-substitution effect Resistivity Susceptibility
Transport and magnetic properties of electron-doped superconducting cuprates Eu1.85Ce0.15Cu1-yZnyO4+α-δ (ECCZO) with y = 0, 0.01, 0.02 and 0.05 have been studied from electrical resistivity and magnetic susceptibility measurements, in order to elucidate the effect of partially Zn-substitution for Cu to its superconductivity and localization of electron in normal state. It has been found that the onset of the critical temperature (Tc) from electrical resistivity and magnetic susceptibility measurements was observed at 13 K for y = 0 and δ values of 0.095. With increasing Zn concentration, the onset of Tc disappeared, indicating the destruction of superconductivity properties by Zn. Moreover, 0.01 of Zn substitution for Cu decreased radius of localization of electron (r) in normal state at low temperatures that may related to the evident of stripe-pinning effects by Zn in electron-doped system of ECCZO. Analysis of magnetic susceptibility data in normal state found a Zn-induced local moments in electron-doped high-Tc superconducting cuprates of ECCZO as observed in hole-doped cuprates.
1. Introduction Electron-doped superconducting cuprate has been one of interesting materials to be studied in order to elucidate mechanism of superconductivity in high Tc superconducting cuprates (HTSC). There are two types HTSC, namely, hole- and electron-doped cuprates. Comparison of some physical properties in both types has attracted research interest to clarify the origin of superconductivity. For holedoped cuprates, some papers reported various physical properties including the study of magnetism, electrical and structure properties [1–7]. However, the number of publications for electron-doped superconducting cuprates is still limited due to the difficulty in preparing the samples. For instance, superconductivity and magnetic properties in electron-doped cuprates strongly depend not only on charge carrier but also on the amount of removal of excess oxygen [8–15]. The study of relationship between magnetism and superconductivity from the effects of impurities on the Cu-spin dynamics was also intensively studied in hole- and electron-doped cuprates. In holedoped cuprates, it was found that nonmagnetic impurities of Zn suppressed superconducting volume fraction more markedly than by magnetic impurity of Ni [5,16]. Substitution of Zn to Cu in this system also tended to induce the slowing down of the Cu-spin fluctuations in
⁎
the entire superconducting regime, attributed to the pinning and stabilization of the dynamically fluctuating stripes [4,17,18]. The strong pinning of Zn in hole-doped cuprates can be described using the stripe model [19,20]. Contrastively, the Zn-induced slowing down of Cu-spin fluctuations was not observed in the electron-doped system of Pr1-xLaCexCu1-yZnyO4 from μSR experiments [9]. One of possible reasons is the effect of Pr3+ moments on the μSR spectra may be stronger than that of a small amount of Zn impurities. Therefore, to make it clearly understood, it is important to study another system of electrondoped cuprates without Pr3+ moments [9]. In this paper, we reported the temperature dependence of electrical resistivity and magnetic susceptibility of electron-doped cuprates Eu1.85Ce0.15Cu1-yZnyO4+α-δ (ECCZO) with y = 0–0.05, in order to investigate effect of Zn substitution to its superconductivity and localization of electron that may related to the stripe-pinning effect. 2. Experimental Polycrystalline samples of ECCZO with y = 0, 0.01, 0.02, and 0.05 were prepared by the ordinary solid-state reaction method [9,13]. Annealing in flowing Ar gas at various temperatures in a range of 900 °C–950 °C for 10 h–15 h was performed in order to remove the
Corresponding author. E-mail address: [email protected] (Risdiana).
https://doi.org/10.1016/j.physc.2018.12.007 Received 12 October 2016; Received in revised form 17 December 2018; Accepted 26 December 2018 Available online 27 December 2018 0921-4534/ © 2018 Elsevier B.V. All rights reserved.
Physica C: Superconductivity and its applications 557 (2019) 41–43
Risdiana et al.
Fig 1. Temperature dependence on normalized electrical resistivity of ρ/ρ300K (a), (1/T)1/4 versus ln ρ (b) and (c) Zn concentration (y) dependence on radius of localization (r) of electron for Eu1.85Ce0.15Cu1-yZnyO4+α-δ with y = 0, 0.01, 0.02, 0.05 and various δ values.
doped and electron-doped cuprates [4,9]. The transport properties in non superconducting state can be studied by calculating the effect of Zn concentration to its radius of localization of electron (r) using variable range hopping mechanism as expressed in Eq. (1).
(T ) =
0 exp
T0 T
1 4
,
(1)
where ρ0 and T0 are resistivity and temperature characteristic in the ground state. T0 can be equal to 1/r3 where r is radius of localization of electron. Fig. 1(b) shows temperature dependence on resistivity plotted as (1/ T)1/4 versus ln ρ for ECCZO at low temperatures in between 13 and 30 K. Solid lines indicating the best-fit results was obtained using Eq. (1). Fig. 1(c) shows Zn concentration (y) dependence on r extracted from Fig 1(b). The value of r started to decrease significantly when Cu was substituted by 0.01 of Zn. This result may related to the stripe pinning by Zn as observed in hole-doped cuprates [4,17,18]. This result also has good agreement with the evident of charge ordering in electron-doped cuprates [23] that was pinned by 0.01 of Zn. With increasing y to 0.02, the value of r increases and then almost constant when the value of y was changed from 0.02 to 0.05. It may due to the destruction of the stripe or charge ordering by large concentration of Zn as in the case of hole-doped cuprates [4,19,20]. Fig. 2 shows temperature dependence on magnetic susceptibility (χ) of ECCZO in a magnetic field of 5 Oe on field cooling. The sample with y = 0 shows bulk superconductivity with Tc∼13 K. The onset Tc from magnetic susceptibility measurement is similar with the value of Tc from electrical resistivity measurement [22]. With increasing Zn concentration, the onset of Tc disappeared. The value of magnetic susceptibility in normal state is almost temperature independent in all samples. The temperature-independent of magnetic susceptibility (χ0) was subtracted from χ. The difference in value of χ0 is quite small compared to the value of χ. In detail, plotting graphs of 1/χ against temperature in normal state at temperatures in between 13 and 30 K are displayed in the insert of Fig. 2. It is observed that the gradient of 1/χ decreases with the Zn substitution, indicating the increase in the Curie constant with the Zn substitution. That is, the present results may show Zn-induced local moments, which is consistent with the NMR data in hole-doped cuprates of YBa2(Cu1-yZny)3O6+x [17].
Fig 2. Temperature dependence on magnetic susceptibility χ of Eu1.85Ce0.15Cu1-yZnyO4+α−δ with y = 0, 0.01, 0.02, 0.05 and various δ values.
excess oxygen (α) at the so-called apical site. The value of removed oxygen (δ) was estimated from the weight change due to annealing [9,21]. All samples were checked by the powder x-ray diffraction measurements and found that the samples were in a single phase. Electrical-resistivity and DC magnetic-susceptibility measurements were carried out to know the superconducting transition temperature (Tc), transport and magnetic properties. The electrical resistivity was measured with DC current in a four-probe configuration at temperatures from 4.2 to 300 K. DC magnetic-susceptibility measurements were carried out at low temperatures down to 2 K using a standard SQUID magnetometer in a magnetic field of 5 Oe on field cooling in Graduate School of Engineering, Tohoku University, Japan. 3. Results and discussion Fig. 1(a) shows temperature dependence on normalized electrical resistivity (ρ/ρ300K) of ECCZO with y = 0, 0.01, 0.02, 0.05 and δ values of 0.095, 0.090, 0.107, 0.045. Onset of Tc was observed at about 13 K for y = 0 [22]. For ECCZO with y = 0.01, 0.02 and 0.05, temperature dependence on normalized electrical resistivity shows semiconductinglike behavior of ρ-T with no sign of onset of Tc. These results show the destruction of superconductivity properties by Zn. These phenomena were also observed in other superconducting cuprates both in hole-
4. Conclusion We prepared high quality polycrystalline samples and studied the transport and magnetic properties of electron-doped high-Tc 42
Physica C: Superconductivity and its applications 557 (2019) 41–43
Risdiana et al.
superconducting cuprates Eu1.85Ce0.15Cu1-yZnyO4 with y = 0, 0.01, 0.02, 0.05 and various δ values. Onset of Tc is observed in Eu1.85Ce0.15Cu1-yZnyO4+α−δ with y = 0 at about 13 K for δ values of 0.095. For Eu1.85Ce0.15Cu1-yZnyO4+α−δ with y = 0.01, 0.02 and 0.05, temperature dependence on electrical resistivity exhibited semiconducting-like behavior of ρ-T with no sign of Tc. It is also found that the value of r started to decrease significantly when Cu was substituted by 0.01 of Zn that may related to the stripe pinning by Zn. The onset Tc from magnetic susceptibility measurement is similar with the value of Tc from electrical resistivity measurement. With increasing Zn concentration, the onset of Tc from magnetic susceptibility also disappeared. Detail analysis of magnetic susceptibility data in normal state found a Zn-induced local moments in electron-doped high-Tc superconducting cuprates Eu1.85Ce0.15Cu1-yZnyO4+α−δ as observed in holedoped cuprates. The present results show that partially Zn subsitution for Cu in electron-doped system of Eu1.85Ce0.15Cu1-yZnyO4+α−δ not only destructed superconductivity properties but also showed the evident of stripe-pinning effects.
(1995) 561. [2] K. Yamada, C.H. Lee, K. Kurahashi, J. Wada, S. Wakimoto, S. Ueki, H. Kimura, Y. Endoh, S. Hosoya, G. Shirane, R.J. Birgeneau, M. Greven, M.A. Kastner, Y.J. Kim, Phys. Rev. B 57 (1998) 6165. [3] K. Suzuki, T. Adachi, Y. Tanabe, Y. Koike, T. Kawamata, Risdiana, T. Suzuki, I. Watanabe, Phys. Rev. B 82 (2010) 054519. [4] Risdiana, Y. Tanabe, K. Omori, T. Suzuki, I. Watanabe, A. Koda, W. Higemoto, Y. Koike, Phys. Rev. B 77 (2008) 054516. [5] T. Adachi, N. Oki, Risdiana, S. Yairi, Y. Koike, I. Watanabe, Phys. Rev. B 78 (2008) 134515. [6] Y. Koike, T. Adachi, N. Oki, Risdiana, M. Yamazaki, T. Kawamata, T. Noji, K. Kudo, N. Kobayashi, I. Watanabe, K. Nagamine, Physica C 426–431 (2005) 189. [7] L. Miu, A.M. Ionescu, I Ivan, T. Miu, T. Adachi, K. Omori, Y. Koike, Physica C 519 (2015) 79. [8] Y. Tokura, H. Takagi, S. Uchida, Nature 337 (1989) 345. [9] Risdiana, T. Adachi, N. Oki, Y. Koike, T. Suzuki, I. Watanabe, Phys. Rev. B 82 (2010) 014506. [10] N.P. Armitage, P. Fournier, R.L. Greene, Rev. Mod. Phys. 82 (2010) 2421. [11] Y. Krockenberger, H. Yamamoto, A. Tsukada, M. Mitsuhashi, M. Naito, Phys. Rev. B 85 (2012) 184502. [12] T. Adachi, Y. Mori, A. Takahashi, M. Kato, T. Nishizaki, T. Sasaki, N. Kobayashi, Y. Koike, J. Phys. Soc. Jpn. 82 (2013) 063713. [13] Risdiana, L. Safriani, W.A. Somantri, T. Saragi, T. Adachi, I. Kawasaki, I. Watanabe, Y. Koike, Adv. Mater. Res. 896 (2014) 354. [14] T.B. Charikova, N.G. Shelushinina, G.I. Harus, D.S. Petukhov, O.E. Petukhova, A.A. Ivanov, Physica C 525-526 (2016) 78. [15] M. Yamamoto, Y. Kohori, H. Fukazawa, A. Takahashi, T. Ohgi, T. Adachi, Y. Koike, J. Phys. Soc. Jpn. 85 (2016) 024708. [16] T. Adachi, N. Oki, Risdiana, S. Yairi, Y. Koike, I. Watanabe, Physica C 460–462 (2007) 1172. [17] A.V. Mahajan, H. Alloul, G. Collin, J.F. Marucco, Phys. Rev. Lett. 72 (1994) 3100. [18] C.M. Smith, A.H.C. Neto, A.V. Balatsky, Phys. Rev. Lett. 87 (2001) 177010. [19] T. Adachi, S. Yairi, Y. Koike, I. Watanabe, K. Nagamine, Phys. Rev. B 70 (2004) 060504(R). [20] T. Adachi, S. Yairi, K. Takahashi, Y. Koike, I. Watanabe, K. Nagamine, Phys. Rev. B 69 (2004) 184507. [21] M. Fujita, T. Kubo, S. Kuroshima, T. Uefuji, K. Kawashima, K. Yamada, I. Watanabe, K. Nagamine, Phys. Rev. B 67 (2003) 014514. [22] Risdiana, S. Pratiwi, D. Suhendar, W.A. Somantri, L. Safriani, T. Saragi, AIP Conf. Proc. 1712 (2016) 050020. [23] E.H. da Silva Neto, R. Comin, F. He, R. Sutarto, Y. Jiang, R.L. Greene, G.A. Sawatzky, A. Damascelli, Science 347 (2015) 282.
Acknowledgments We would like to thank Y. Koike, T. Adachi, M. Kato, T. Noji, T. Kawamata and H. Sato for their technical support in the powder x-ray diffraction, electrical-resistivity and magnetic-susceptibility measurements at Tohoku University, Japan. These works were supported by Academic Leadership Grant of Padjadjaran University. Part of this work was also supported by research grant of International Research Collaboration and Scientific Publication 2015 (No: 393/UN6.R/PL/ 2015), 2016 (No: 431/UN6.3.1/PL/2016), 2017 (No: 718/UN6.3.1/PL/ 2017), 2018 (1133/ UN6.D/LT/2018). References [1] J.M. Tranquada, B.J. Sternlieb, J.D. Axe, Y. Nakamura, S. Uchida, Nature 375
43