В четверг 31 октября в 14:00 в 226.5 ЛК в рамках курса "Современные проблемы квантовой физики" состоится семинар.
С докладами выступят:
Зотова Юлия Игоревна, научный сотрудник лаборатории искусственных квантовых систем МФТИ (группа О.В. Астафьева). Тема доклада: Компактные микроволновые устройства для джозефсоновских квантовых цепей (по мотивам кандидатской диссертации). Автореферат и диссертацию можно найти на сайте МФТИ: https://mipt.ru/institute/departments/dissertatio/soiskateli/fm/zotova-yuliya-igorevna
Шеина Валерия
с докладом на тему: Dynamics of coupled Ti spins on ultra-thin MgO layers probed by ESR-STМ
Scanning tunneling microscopy (STM) combined with electron spin resonance (ESR) enables a coherent control of atomic spins on surfaces. Recently, introduction of a 'remote' spin [1], which is free from the tunneling-induced scattering, has shown a spin relaxation time (T1) significantly improved, but still limited by strong substrate scattering [2]. In this talk,we first present an ESR-STM study on the spin relaxation of coupled Ti atoms (S = 1/2) on 3 ML MgO. A remote Tishowed T1 of ~10 s, longer by 2 orders of magnitude than a remote Ti on 2 ML MgO [2], which is well understood by the enhanced decoupling from the metallic substrate. However, a 'sensor' spin, positioned in the tunnel junction, showed T1 of ~100 ns where its dynamics is still strongly governed by scattering with tip and tunneling current [3]. Second, we introduce a present work on controlling the dynamics of the remote spin. The tip indeed generates an unbalance in dynamics of coupled Ti spins by introducing strong dissipation at the sensor side. We show that, by tuning energy eigenstates of the two-spin quantum system, the remote spin dynamics can be decoupled or coupled from that of the sensor spin via the exchange channel between the two. This study is essential for quantum information processing and quantum simulation exploiting such two coupled spins in unbalanced environment.
References:
[1] S. Phark et al. ACS Nano 17, 14144–14151 (2023).
[2] Y. Wang et al. Science 382, 6666 (2023).
[3] W. Paul et al. Nature Phys. 13, 403–407 (2017).