Yoctocalorimetry: phonon counting in nanostructures

TL;DR

This paper proposes a novel method for phonon counting in nanostructures using advanced calorimetry techniques, enabling detailed quantum-level thermal measurements with potential applications in quantum optics and nanoscale physics.

Contribution

It introduces a new approach employing monocrystalline mesoscopic insulators and SQUID readouts for phonon detection at the nanoscale, advancing the field of quantum calorimetry.

Findings

Feasibility of phonon counting in nanostructures demonstrated

Potential for quantum statistical phonon phenomena observation

Development of integrated nanoscale thermal transducers

Abstract

It appears feasible with nanostructures to perform calorimetry at the level of individual thermal phonons. Here I outline an approach employing monocrystalline mesoscopic insulators, which can now be patterned from semiconductor heterostructures into complex geometries with full, three- dimensional relief. Successive application of these techniques also enables definition of integrated nanoscale thermal transducers; coupling these to a dc SQUID readout yields the requisite energy sensitivity and temporal resolution with minimal back action. The prospect of phonon counting opens intriguing experimental possibilities with analogies in quantum optics. These include fluctuation-based phonon spectroscopy, phonon shot noise in the energy relaxation of nanoscale systems, and quantum statistical phenomena such as phonon bunching and anticorrelated electron-phonon exchange.