Longitudinal piezoelectric resonant photoelastic modulator for efficient intensity modulation at megahertz frequencies
Journal article, 2022

Intensity modulators are an essential component in optics for controlling free-space beams. Many applications require the intensity of a free-space beam to be modulated at a single frequency, including wide-field lock-in detection for sensitive measurements, mode-locking in lasers, and phase-shift time-of-flight imaging (LiDAR). Here, we report a new type of single frequency intensity modulator that we refer to as a longitudinal piezoelectric resonant photoelastic modulator. The modulator consists of a thin lithium niobate wafer coated with transparent surface electrodes. One of the fundamental acoustic modes of the modulator is excited through the surface electrodes, confining an acoustic standing wave to the electrode region. The modulator is placed between optical polarizers; light propagating through the modulator and polarizers is intensity modulated with a wide acceptance angle and record breaking modulation efficiency in the megahertz frequency regime. As an illustration of the potential of our approach, we show that the proposed modulator can be integrated with a standard image sensor to effectively convert it into a time-of-flight imaging system.

Author

Okan Atalar

Stanford University

Raphaël Van Laer

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Technology

E.L. Ginzton Lab

Amir H. Safavi-Naeini

E.L. Ginzton Lab

Amin Arbabian

Stanford University

Nature Communications

2041-1723 (ISSN)

Vol. 13 1 1526

Subject Categories

Medical Laboratory and Measurements Technologies

Atom and Molecular Physics and Optics

Other Physics Topics

DOI

10.1038/s41467-022-29204-9

More information

Latest update

4/7/2022 1