Cho, Seong Won Lee, Young Woong Kim, Sang Heon Han, Seungwu Kim, Inho Park, Jong-Keuk Kwak, Joon Young Kim, Jaewook Jeong, YeonJoo Hwang, Gyu Weon Lee, Kyeong Seok Park, Seongsik Lee, Suyoun 2024-01-19T09:00:46Z 2024-01-19T09:00:46Z 2023-06-29 2023-09 0925-8388 https://pubs.kist.re.kr/handle/201004/113358 Featured with the large Rashba constant (alpha R -4.2 eV angstrom) coupled with the ferroelectricity, GeTe has attracted much interest, proposing novel energy-efficient spintronic devices. However, those approaches are ham-pered by the high hole density of GeTe around 1020-1021 cm-3, which deteriorates both the ferroelectricity and the bulk Rashba effect of GeTe. To solve this problem, we have investigated the superlattices composed of Bi2Te3 and GeTe ([BT|GT] SL), the former of which is known as a topological insulator (TI) with typically n- type conduction and strong spin-orbit coupling. We have investigated the magnetotransport properties of 25 [BTx|GTy]z SLs with varying thicknesses (x, y: the thickness in the multiples of the unit cell of the re-spective layer) of each layer and the repetition number (z) systematically. We have observed a minimum carrier density of 5.7 x 1019 cm-3 in [BT6|GeTe6]6 superlattice sample smaller than that (-4.4 x1020 cm-3) of GeTe single film by an order. In addition, we have found that some [BT|GT] SLs with reduced carrier density have a larger Rashba constant compared to that of a single GeTe film. This is explained by the change of the spin polarization which can be modulated by the Fermi level in the Rashba band. These results provide a viable way to realize robust ferroelectricity and strong SOC in GeTe-related material systems simulta-neously.(c) 2023 Elsevier B.V. All rights reserved. English Elsevier BV Reduction of carrier density and enhancement of the bulk Rashba spin-orbit coupling strength in Bi2Te3/GeTe superlattices Article 10.1016/j.jallcom.2023.170444 1 Journal of Alloys and Compounds, v.957 Journal of Alloys and Compounds 957 N scie scopus 001004246300001 2-s2.0-85158857750 Chemistry, Physical Materials Science, Multidisciplinary Metallurgy & Metallurgical Engineering Chemistry Materials Science Metallurgy & Metallurgical Engineering Article HIGH THERMOELECTRIC PERFORMANCE TOPOLOGICAL-INSULATOR PHASE-TRANSITION GETE SEMICONDUCTORS SPINTRONICS REALIZATION SUPPRESSION RELAXATION CHALLENGES Ferroelectric Rashba semiconductor Rashba effect Charge compensation Superlattice Weak antilocalization