1.

Record Nr.

UNINA9910765483303321

Autore

Hillberry Logan Edward

Titolo

Optically Trapped Microspheres as Sensors of Mass and Sound : Brownian Motion as Both Signal and Noise / / by Logan Edward Hillberry

Pubbl/distr/stampa

Cham : , : Springer Nature Switzerland : , : Imprint : Springer, , 2023

ISBN

3-031-44332-2

Edizione

[1st ed. 2023.]

Descrizione fisica

1 online resource (124 pages)

Collana

Springer Theses, Recognizing Outstanding Ph.D. Research, , 2190-5061

Disciplina

539

530.8

Soggetti

Atoms

Metrology

Optics

Measurement

Measuring instruments

Acoustics

Statistical Physics

Metrology and Fundamental Constants

Light-Matter Interaction

Measurement Science and Instrumentation

Lingua di pubblicazione

Inglese

Formato

Materiale a stampa

Livello bibliografico

Monografia

Nota di contenuto

Chapter 1. Introduction -- Chapter 2. Technical Background -- Chapter 3. Experimental set-up -- Chapter 4. Results -- Chapter 5. Conclusions.

Sommario/riassunto

This thesis makes significant advances in the use of microspheres in optical traps as highly precise sensing platforms. While optically trapped microspheres have recently proven their dominance in aqueous and vacuum environments, achieving state-of-the-art measurements of miniscule forces and torques, their sensitivity to perturbations in air has remained relatively unexplored. This thesis shows that, by uniquely operating in air and measuring its thermally-fluctuating instantaneous



velocity, an optically trapped microsphere is an ultra-sensitive probe of both mass and sound. The mass of the microsphere is determined with similar accuracy to competitive methods but in a fraction of the measurement time and all while maintaining thermal equilibrium, unlike alternative methods. As an acoustic transducer, the air-based microsphere is uniquely sensitive to the velocity of sound, as opposed to the pressure measured by a traditional microphone. By comparison to state-of-the-art commercially-available velocity and pressure sensors, including the world’s smallest measurement microphone, the microsphere sensing modality is shown to be both accurate and to have superior sensitivity at high frequencies. Applications for such high-frequency acoustic sensing include dosage monitoring in proton therapy for cancer and event discrimination in bubble chamber searches for dark matter. In addition to reporting these scientific results, the thesis is pedagogically organized to present the relevant history, theory, and technology in a straightforward way.