2018年第65回応用物理学会春季学術講演会

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CS コードシェアセッション » CS6 10.1 新物質・新機能創成(作製・評価技術),10.2 スピン基盤技術・萌芽的デバイス技術,10.3 スピンデバイス・磁気メモリ・ストレージ技術のコードシェアセッション

[19a-D104-1~11] CS6 10.1 新物質・新機能創成(作製・評価技術),10.2 スピン基盤技術・萌芽的デバイス技術,10.3 スピンデバイス・磁気メモリ・ストレージ技術のコードシェアセッション

2018年3月19日(月) 09:00 〜 12:00 D104 (56-104)

野崎 友大(東北大)

11:45 〜 12:00

[19a-D104-11] Electric Field Controlled Hall and Thermo-power Effects in La0.7Ca0.3MnO3 Thin Film

〇(P)Himanshu Sharma1,2、C. V. Tomy3、Ashwin Tulapurkar3、Masaki Mizuguchi1,2 (1.IMR, Tohoku Univ.,、2.CREST-JST、3.IIT Bombay, India)

キーワード:Electric Field effect, Nernst effect, Hall effect

The electric field effect in manganites (i.e., electric field control of magnetization, magnetic anisotropy, domain structure, spin polarization, critical temperatures, etc) recently attracted much attention due to its potential applications in spintronics, multiferroic and magnetoelectronics [1-3]. Also, substantial research efforts have been devoted in spin caloritronics to investigate the interplay of spin and thermoelectric transport phenomena in manganites [4]. What have not yet been investigated are changes in Hall effect [5], possibly the carrier density [5] and the thermal counterpart of the Hall effect (i.e., the Nernst effect [4]) in this material, when the electric field is applied on manganite films.
Here, we present an approach to control the Hall effect and transverse thermopower (i.e., Nernst effect) of manganites. Using a field-effect gated device, we aimed to tune the Hall and Nernst effect of manganite (i.e., La0.7Ca0.3MnO3) channel.
We have deposited thin films of mangnites (i.e., La0.7Ca0.3MnO3) on STO (001) substrates by the pulsed laser deposition (PLD) method. For measuring the Hall and Nernst effects, these thin films were converted into patterned Hall bar structures, by using the optical lithography and ion-milling process. Subsequently, a layer of Al2O3 of about 60 nm thickness was deposited on top of this manganite thin film using ion beam sputter (IBS) in order to use it as a gate electrode. For Nernst measurements the Hall bar structure was mounted on a platform to obtain the required temperature gradient. A cryostat of physical property measurement system (PPMS-Quantum Design Inc.) was used for obtaining temperature and magnetic field variations. The electric field effect of manganite films will be discussed in detail.
References
[1] Q. P. Chen, J. J. Yang, Y. G. Zhao, S. Zhang, J. W. Wang, M. H. Zhu, Y. Yu, X. Z. Zhang, Zhu Wang, Bin Yang, D. Xie, and T. L. Ren, Appl. Phys. Lett., 98,172507 (2011).
[2] H. Sharma, A. Tulapurkar, C. V. Tomy, Mate. Chem. Phys., 186, 523 (2017).
[3] T. Wu, S. B. Ogale, J. E. Garrison, B. Nagaraj, Amlan Biswas, Z. Chen, R. L. Greene, R. Ramesh, T. Venkatesan and A. J. Millis, Phy. Rev. Lett., 86, 5998 (2001).
[4] H. Sharma, H. Bana, A. Tulapurkar, C. V. Tomy, Mate. Chem. Phys., 180, 390 (2016).
[5] I. Mubeen Dildar, C. Beekman, Xin He, and J. Aarts, Phys. Rev. B., 85, 205103 (2012).