Optical coherence of 166Er:7LiYF4 crystal below 1 K. (19th February 2018)

• Record Type: Journal Article
• Authors: Kukharchyk, N; Sholokhov, D; Morozov, O; Korableva, S L; Kalachev, A A; Bushev, P A
• Is Part Of: New journal of physics. Volume 20:Number 2(2018:Feb.)
• Publication Date: 2018-02-19
• Subjects: Rare-earth doped crystals -- quantum information architectures & platforms -- optical coherence -- spin relaxation -- optical quantum memory -- spin coherence; Physics -- Periodicals; Physics; Periodicals; 530.05
• DOI: 10.1088/1367-2630/aaa7e4
• Languages: English
• ISSNs: 1367-2630

Abstract

Abstract: We explore optical coherence and spin dynamics of an isotopically purified 166 Er: 7 LiYF4 crystal below 1 K and at weak magnetic fields < 0.3T. Crystals were grown in our lab and demonstrate narrow inhomogeneous optical broadening down to 16 MHz. Solid-state atomic ensembles with such narrow linewidths are very attractive for implementing of off-resonant Raman quantum memory and for the interfacing of superconducting quantum circuits and telecom C-band optical photons. Both applications require a low magnetic field of ∼10 mT. However, at conventional experimental temperatures T > 1.5 K, optical coherence of Er:LYF crystal attains ≃ 10 μ s time scale only at strong magnetic fields above 1.5 T. In the present work, we demonstrate that the deep freezing of Er:LYF crystal below 1 K results in the increase of optical coherence time to ≃ 100 μ s at weak fields.