Home > 게시판 > 세미나
양자물질초전도체창의연구소에서 최은미 박사님을 초청하여 아래와 같이 세미나를 개최합니다.
학과 구성원 여러분의 많은 참석을 부탁드립니다.
○ Date/time: 2019. 08. 14(Wed.) 11:00
○ Place: 삼성학술정보관 7층
○ Speaker: 최 은 미 박사 (前)Post-Doctoral researcher, University of Cambridge, UK)
○ Title: 3D-strain induced superconductivity in La2CuO4+δ using a simple vertically aligned nanocomposite approach
○ Abstract: A long-term goal for superconductors is to increase the superconducting transition temperature, TC. In cuprates, TC depends strongly on the out-of-plane Cu-apical oxygen distance, and the in-plane Cu-O distance. High out-of-plane and the in-plane parameters are both individually linked to higher TC, but to date they have not been achieved together.
Herein, I introduce a simple and unique self-assembled approach to 3D-strain engineering. In simply-grown, self-assembled, vertically aligned thin film nanocomposite (VAN) thin films of La2CuO4+δ+LaCuO3 grown on SrTiO3, by strongly increasing the out-of-plane distances without reducing in-plane distances, we achieve superconductivity up to 50 K. Our VAN approach leads to strong vertical strain of ~50 nm La2CuO4+δ nanopillars by a LaCuO3 matrix in which the La2CuO4+δ is embedded. The LaCuO3 expands the La2CuO4+δ out-of-plane along the interfaces spaced every ~50 nm, the strained region spreading ~10 nm laterally from each interface. A TC of 50 K has only been achieved before at single atomic layer interfaces in complex heterostructures. Otherwise, in plain or doped La2CuO4+δ films, TC is 35 K or below. In addition, no additional process to supply excess oxygen, e.g. by ozone annealing, was required as is the case for La2CuO4+δ films studied previously. Our work represents a new, self-assembled approach to 3D-strain engineering of cuprates to enhance TC. Our proof-of-concept work represents an entirely new approach to increasing TC in cuprates or other superconductors.1
In addition, I introduce our promising result of weak magnetic signatures of superconductivity up to 120 K from DC magnetic susceptibility measurements, which can be turned on and off by changing oxygen content.
1. Choi, E.-M. et al. 3D strain-induced superconductivity in La2CuO4+δ using a simple vertically aligned nanocomposite approach. Sci. Adv. 5, eaav5532 (2019).
|공지||<12/8(Thu.) 11:00am>노벨상 소개 강연 - 2016년 노벨 물리학상: 위상 응집 물리의 탄생||2016.11.28||1090478|
|42||<8/19(Mon) 14:00 ~ >Exploring topological matter in an atomic quantum simulator||2019.07.26||81883|
|»||<8/14(Wed.)>3D-strain induced superconductivity in La2CuO4+δ using a simple vertically aligned nanocomposite approach||2019.08.13||71959|
|40||<8/19(Mon) 13:30 ~ >Detection of cosmic rays in the PeV to EeV energy range||2019.08.16||101874|
|39||<8/26(Mon) 14:00 ~ >Constructing viable models of bouncing scenarios||2019.08.20||60355|
|38||<8/30(Fri) 16:00 ~ >Structures of light neutron-rich nuclei, 17,19C||2019.08.22||93453|
|37||<9/2(Mon) 15:00 ~ >Status of the KM3NeT Deep Sea Neutrino Telescope||2019.08.26||84195|
|36||<9/17(Tue) 4:00 pm ~ >Dynamics of multiple-Q spin textures and its effect on electronic state||2019.09.10||67148|
|35||<9/24(Tue) 4:00 pm ~ > Structure Formation with Two Periods of Inflation: Beyond plain LCDM||2019.09.17||52282|
|34||<9/26(Thu.) 4:30 pm ~ > Neutrino Physics and Dark Matter search in IBS||2019.09.24||112221|
|33||<10/1(Tue.) Mini-Workshop on BSM Physics with Neutrino Detectors||2019.09.30||91807|
|32||<10/22(Tue.)>To p or not to p? – 17O NMR of Sr2RuO4 under strain||2019.10.17||104010|
|31||<12/6(Fri.)>topological phase transitions in Kitaev quantum spin liquids.||2019.12.04||78950|
|30||<12/10(Tue.)> Investigating dark matter signals at neutrino telescopes||2019.12.06||106910|
|29||<12/17(Tue.)> Nuclear spectroscopy with low energy reaction thermal neutrons in ILL||2019.12.17||77064|
|28||<2/17(Mon.)> Magneto-optical study of the Dirac semimetal Cd3As2 in Voigt geometry||2020.02.11||94129|
|27||<8/1(Sat.)> Recent Advances in Deep Learning||2020.07.29||38287|
|26||<11/5(Thu.)> Higher Spin Cooper Pairs||2020.10.27||117283|
|25||<Jan.14(Thu.)>Oxygen sponge effects for epitaxial manganite thin film design||2021.01.11||248671|
|24||<Jan.28(Thu.)>X-ray Absorption Spectroscopy Study of Amorphous Oxide Thin Films||2021.01.27||113896|
|23||<Feb.18(Thu.)> Hund's metallicity in the vicinity of a Van Hove singularity / Correlated topological phases in strongly correlated heterostructures||2021.02.16||201570|