Publications (32)
A broadband silicon photonic-integrated-circuit based RF spectrum analyzer with 10 MHz spectral resolution
Brandon Redding, Joseph B. Murray, Matthew J. Murray +10
Designing miniaturized optical spectrometers is an increasingly active area of research as spectrometers are crucial components for a wide range of applications including chemical…
Efficient method for controlling the spatial coherence of a laser
Micha Nixon, Brandon Redding, Asher Friesem +2
An efficient method to tune the spatial coherence of a degenerate laser over a broad range with minimum variation in the total output power is presented. It is based on varying the…
Using a multimode fiber as a high resolution, low loss spectrometer
Brandon Redding, Hui Cao
We propose and demonstrate that a conventional multimode fiber can function as a high resolution, low loss spectrometer. The proposed spectrometer consists only of the fiber and a…
Principal modes in multimode fibers: exploring the crossover from weak to strong mode coupling
Wen Xiong, Philipp Ambichl, Yaron Bromberg +3
We present experimental and numerical studies on principal modes in a multimode fiber with mode coupling. By applying external stress to the fiber and gradually adjusting the stres…
Coherence switching of a degenerate VECSEL for multimodality imaging
Sebastian Knitter, Changgeng Liu, Brandon Redding +3
We demonstrate a VECSEL (vertical external cavity surface emitting laser) based degenerate source with an adjustable degree of spatial coherence that is electrically pumped, mechan…
Pump-Controlled Modal Interactions in Microdisk Lasers
Seng Fatt Liew, Li Ge, Brandon Redding +2
We demonstrate an effective control of nonlinear interactions of lasing modes in a semiconductor microdisk cavity by shaping the pump profile. A target mode is selected at the expe…
Deep learning of ultrafast pulses with a multimode fiber
Wen Xiong, Brandon Redding, Shai Gertler +3
Characterizing ultrashort optical pulses has always been a critical but difficult task, which has a broad range of applications. We propose and demonstrate a self-referenced method…
Active control of emission directionality of semiconductor microdisk lasers
Seng Fatt Liew, Brandon Redding, Li Ge +2
We demonstrate lasing mode selection in nearly circular semiconductor microdisks by shaping the spatial profile of optical pump. Despite of strong mode overlap, adaptive pumping su…
Evanescently coupled multimode spiral spectrometer
Brandon Redding, Seng Fatt Liew, Yaron Bromberg +2
We designed a high-resolution compact spectrometer based on an evanescently-coupled multimode spiral waveguide. Interference between the modes in the waveguide forms a wavelength-d…
Position-dependent diffusion of light in disordered waveguides
Alexey G. Yamilov, Raktim Sarma, Brandon Redding +3
Diffusion has been widely used to describe a random walk of particles or waves, and it requires only one parameter -- the diffusion constant. For waves, however, diffusion is an ap…
On-Chip Random Spectrometer
Brandon Redding, Seng Fatt Liew, Raktim Sarma
Light scattering in disordered media has been studied extensively due to its prevalence in natural and artificial systems [1]. In the field of photonics most of the research has fo…
Multimode optical fiber based spectrometers
Brandon Redding, Sebastien M. Popoff, Hui Cao
A standard multimode optical fiber can be used as a general purpose spectrometer after calibrating the wavelength dependent speckle patterns produced by interference between the gu…
Controlling mode competition by tailoring the spatial pump distribution in a laser: A resonance-based approach
Alexander Cerjan, Brandon Redding, Li Ge +3
We introduce a simplified version of the steady-state ab initio laser theory for calculating the effects of mode competition in continuous wave lasers using the passive cavity reso…
Extreme Sensitivity of Output Directionality to Boundary Perturbation in Wavelength-Scale Microcavities
Li Ge, Qinghai Song, Brandon Redding +1
We report a surprising observation that the output directionality from wavelength-scale optical microcavities displays extreme sensitivity to deformations of the cavity shape. A va…
Integrated Photonic Encoder for Terapixel Image Processing
Xiao Wang, Brandon Redding, Nicholas Karl +5
Modern lens designs are capable of resolving >10 gigapixels, while advances in camera frame-rate and hyperspectral imaging have made Terapixel/s data acquisition a real possibility…
A narrow-band speckle-free light source via random Raman lasing
Brett H. Hokr, Morgan S. Schmidt, Joel N. Bixler +8
Currently, no light source exists which is both narrow-band and speckle-free with sufficient brightness for full-field imaging applications. Light emitting diodes (LEDs) are excell…
Photonic frequency multiplexed next-generation reservoir computer
Nicholas Cox, Joseph Murray, Joseph Hart +1
In this work, we introduce and experimentally demonstrate a photonic frequency-multiplexed next generation reservoir computer (FM-NGRC) capable of performing real-time inference at…
Spatial coherence of random laser emission
Brandon Redding, Michael A. Choma, Hui Cao
We experimentally studied the spatial coherence of random laser emission from dye solutions containing nanoparticles. The spatial coherence, measured in a double-slit experiment, v…
Nonlinear pluggable optics: Digital signal processing-free Intensity Modulated Direct Detection links using analog photonic Next Generation Reservoir Computing
Nicholas Cox, Joseph Murray, Ross T. Schermer +6
In this work, we propose a Nonlinear Pluggable Optic (NLPO) transceiver that combines the low latency and low power consumption of Linear Pluggable Optics (LPO) with the range and…
High-resolution and broadband all-fiber spectrometers
Brandon Redding, Mansoor Alam, Martin Seifert +1
The development of optical fibers has revolutionized telecommunications by enabling long-distance broad-band transmission with minimal loss. In turn, the ubiquity of high-quality l…
Super- and Anti-Principal Modes in Multi-Mode Waveguides
Philipp Ambichl, Wen Xiong, Yaron Bromberg +3
We introduce a new type of states for light in multimode waveguides featuring strongly enhanced or reduced spectral correlations. Based on the experimentally measured multi-spectra…
Photonic next-generation reservoir computer based on distributed feedback in optical fiber
Nicholas Cox, Joseph Murray, Joseph Hart +1
Reservoir computing (RC) is a machine learning paradigm that excels at dynamical systems analysis. Photonic RCs, which perform implicit computation through optical interactions, ha…
Low-loss high-speed speckle reduction using a colloidal dispersion
Brandon Redding, Graham Allen, Eric R. Dufresne +1
We present a simple and robust approach to reduce laser speckle, which has limited the adoption of lasers in imaging and display applications. We use colloidal solutions that can q…
Speckle-free laser imaging
Brandon Redding, Michael A. Choma, Hui Cao
Many imaging applications require increasingly bright illumination sources, motivating the replacement of conventional thermal light sources with light emitting diodes (LEDs), supe…
Fiber optic computing using distributed feedback
Brandon Redding, Joseph B. Murray, Joseph D. Hart +3
The widespread adoption of machine learning and other matrix intensive computing algorithms has inspired renewed interest in analog optical computing, which has the potential to pe…
Remote Key Establishment by Mode Mixing in Multimode Fibres and Optical Reciprocity
Yaron Bromberg, Brandon Redding, Sebastien M. Popoff +1
Disorder and scattering in photonic systems have long been considered a nuisance that should be circumvented. Recently, disorder has been harnessed for a rapidly growing number of…
Broadband multimode fiber spectrometer
Seng Fatt Liew, Brandon Redding, Michael A. Choma +2
A general-purpose all-fiber spectrometer is demonstrated to overcome the trade-off between spectral resolution and bandwidth. By integrating a wavelength division multiplexer with…
Intracavity frequency-doubled degenerate laser
Seng Fatt Liew, Sebastian Knitter, Sascha Weiler +5
We develop a green light source with low spatial coherence via intracavity frequency doubling of a solid-state degenerate laser. The second harmonic emission supports many more tra…
Directional waveguide coupling from a wavelength-scale deformed microdisk laser
Brandon Redding, Li Ge, Glenn S. Solomon +1
We demonstrate uni-directional evanescent coupling of lasing emission from a wavelength-scale deformed microdisk to a waveguide. This is attributed to the Goos-Hänchen shift and F…
Multimode Coupling by Boundary Wave Scattering
Li Ge, Qinghai Song, Brandon Redding +3
We show that coupling among multiple resonances can be conveniently introduced and controlled by boundary wave scattering. We demonstrate this principle in optical microcavities of…
Low-spatial-coherence broadband fiber source for speckle free imaging
Brandon Redding, Peyman Ahmadi, Vadim Mokan +3
We designed and demonstrate a fiber-based amplified spontaneous emission (ASE) source with low spatial coherence, low temporal coherence, and high power per mode. ASE is produced b…
Local chirality of optical waves in ultrasmall resonators
Brandon Redding, Li Ge, Qinghai Song +3
The local chiral symmetry between clockwise (CW) and counter-clockwise (CCW) propagating light in a deformed microcavity can be broken by wave optics effects, which become signific…