Electron spin relaxation of single phosphorus donors in metal-oxide-semiconductor nanoscale devices

Stefanie B. Tenberg, Serwan Asaad, Mateusz T. Madzik, Mark A.I. Johnson, Benjamin Joecker, Arne Laucht, Fay E. Hudson, Kohei M. Itoh, A. Malwin Jakob, Brett C. Johnson, David N. Jamieson, Jeffrey C. McCallum, Andrew S. Dzurak, Robert Joynt, Andrea Morello

Research output: Contribution to journalArticlepeer-review

18 Citations (Scopus)

Abstract

We analyze the electron spin relaxation rate 1/T1 of individual ion-implanted P31 donors in a large set of metal-oxide-semiconductor (MOS) silicon nanoscale devices, with the aim of identifying spin relaxation mechanisms peculiar to the environment of the spins. The measurements are conducted at low temperatures (T≈100 mK) as a function of external magnetic field B0 and donor electrochemical potential μD. We observe a magnetic field dependence of the form 1/T1B05 for B03 T, corresponding to the phonon-induced relaxation typical of donors in the bulk. However, the relaxation rate varies by up to two orders of magnitude between different devices. We attribute these differences to variations in lattice strain at the location of the donor. For B03T, the relaxation rate changes to 1/T1B0 for two devices. This is consistent with relaxation induced by evanescent-wave Johnson noise created by the metal structures fabricated above the donors. At such low fields, where T1>1s, we also observe and quantify the spurious increase of 1/T1 when the electrochemical potential of the spin excited state |↑) comes in proximity to empty states in the charge reservoir, leading to spin-dependent tunneling that resets the spin to |↓). These results provide precious insights into the microscopic phenomena that affect spin relaxation in MOS nanoscale devices, and provide strategies for engineering spin qubits with improved spin lifetimes.

Original languageEnglish
Article number205306
JournalPhysical Review B
Volume99
Issue number20
DOIs
Publication statusPublished - 2019 May 14

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

Fingerprint

Dive into the research topics of 'Electron spin relaxation of single phosphorus donors in metal-oxide-semiconductor nanoscale devices'. Together they form a unique fingerprint.

Cite this