Pulsed Low-Field Electrically Detected Magnetic Resonance

TL;DR

This paper demonstrates that pulsed electrically detected magnetic resonance techniques, traditionally used at high frequencies, are effective at low magnetic fields for studying spin dynamics and hyperfine interactions in silicon-based systems.

Contribution

It extends pulsed EDMR methods to low magnetic fields, showing their feasibility and revealing new insights into spin coherence, Rabi oscillations, and hyperfine interactions at MHz frequencies.

Findings

Pulsed EDMR is feasible at low magnetic fields in the MHz regime.

Rabi frequency scales with magnetic field as predicted by the spin Hamiltonian.

Detection of hydrogen NMR via electron spin echo modulation at low frequencies.

Abstract

We present pulsed electrically detected magnetic resonance (EDMR) measurements at low magnetic fields using posphorus-doped silicon with natural isotope composition as a model system. Our measurements show that pulsed EDMR experiments, well established at X-band frequencies (10 GHz), such as coherent spin rotations, Hahn echoes, and measurements of parallel and antiparallel spin pair life times are also feasible at frequencies in the MHz regime. We find that the Rabi frequency of the coupled 31P electron-nuclear spin system scales with the magnetic field as predicted by the spin Hamiltonian, while the measured spin coherence and recombination times do not strongly depend on the magnetic field in the region investigated. The usefulness of pulsed low-field EDMR for measurements of small hyperfine interactions is demonstrated by electron spin echo envelope modulation measurements of the Pb0 dangling-bond state at the Si/SiO2 interface. A pronounced modulation with a frequency at the free Larmor frequency of hydrogen nuclei was observed for radio frequencies between 38 MHz and 400 MHz, attributed to the nuclear magnetic resonance of hydrogen in an adsorbed layer of water This demonstrates the high sensitivity of low-field EDMR also for spins not directly participating in the spin-dependent transport investigated.