Storage and retrieval of microwave pulses with molecular spin ensembles

Claudio Bonizzoni,Roberta Sessoli,Alberto Ghirri,Lorenzo Sorace,Marco Affronte,Matteo Atzori,Fabio Santanni

doi:10.1038/s41534-020-00296-9

Abstract

Hybrid architectures combining complementary quantum systems will be largely used in quantum technologies and the integration of different components is one of the key issues. Thanks to their long coherence times and the easy manipulation with microwave pulses, electron spins hold a potential for the realization of quantum memories. Here, we test diluted oxovanadium tetraphenyl porphyrin (VO(TPP)) as a prototypical molecular spin system for the Storage/Retrieval of microwave pulses when embedded into planar superconducting microwave resonators. We first investigate the efficiency of several pulse sequences in addressing the spins. The Carr-Purcell and the Uhrig Dynamical Decoupling enhance the memory time up to three times with three π pulses. We then successfully store and retrieve trains of up to 5 small pulses by using a single recovery pulse. These results demonstrate the memory capabilities of molecular spin ensembles when embedded into quantum circuits.

Highlights

Quantum memories are fundamental components in quantum hardware like quantum computers, sensors or repeaters
Hybrid architectures combining complementary quantum systems will be largely used in quantum technologies and the integration of different components is one of the key issues
We use VO(TPP) molecular spin ensembles 2% diluted in a diamagnetic isostructural analogue, oxotitanium tetraphenylporlographic axis of the tetragonal VOTPP crystal, as evidenced by the simulation performed with the EasySpin software[51]

Summary

Introduction

Quantum memories are fundamental components in quantum hardware like quantum computers, sensors or repeaters. The use of individual (natural or artificial) spins is the ultimate goal[10] collective excitations in spin ensembles may preserve and coherently exchange electromagnetic excitations, and eventually quantum information, under optimal conditions[8,9,11,12]. In this context, molecular spins have recently emerged as a new class of quantum systems whose electronic and nuclear spin states and their relative quantum features (including g-factor[13,14], coherence time15–17, “atomic-clock” transitions13,18,19) can be extensively tailored synthetically. Different strategies for encoding quantum information protocols into molecular ensembles[20,21] or single molecules in a spin transistor geometry[22,23] have been developed and experimentally proven

Methods

Results

Conclusion