A5002874119- Advanced Fiber Laser Technologies
- Laser-Matter Interactions and Applications
- Photonic Crystal and Fiber Optics
- Advanced Frequency and Time Standards
- Solid State Laser Technologies
- Photonic and Optical Devices
- Spectroscopy and Laser Applications
- Laser Design and Applications
- Physics of Superconductivity and Magnetism
- Atomic and Subatomic Physics Research
- Semiconductor Lasers and Optical Devices
- Spectroscopy Techniques in Biomedical and Chemical Research
- Advanced Fluorescence Microscopy Techniques
- Advanced Fiber Optic Sensors
- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Topological Materials and Phenomena
- Advanced Chemical Physics Studies
- Advanced Electron Microscopy Techniques and Applications
- Optical Coherence Tomography Applications
- Cold Atom Physics and Bose-Einstein Condensates
- Quantum optics and atomic interactions
- Mass Spectrometry Techniques and Applications
- Electron and X-Ray Spectroscopy Techniques
- Laser-Plasma Interactions and Diagnostics
University of British Columbia
2014-2023
Max Planck Institute for Chemical Physics of Solids
2019
Battelle
2008-2010
University of Colorado Boulder
2000-2007
National Institute of Standards and Technology
2000-2007
Joint Institute for Laboratory Astrophysics
2000-2007
Max Planck Society
2007
University of British Columbia Hospital
2006
Massachusetts Institute of Technology
1995-2005
Alcatel Lucent (Germany)
2000
We stabilized the carrier-envelope phase of pulses emitted by a femtosecond mode-locked laser using powerful tools frequency-domain stabilization. confirmed control pulse-to-pulse temporal cross correlation. This stabilization locks absolute frequencies laser, which we used to perform optical frequency measurements that were directly referenced stable microwave clock.
We demonstrate a great simplification in the long-standing problem of measuring optical frequencies terms cesium primary standard. An air-silica microstructure fiber broadens frequency comb femtosecond laser to span octave from 1064 532 nm, enabling us measure 282 THz an iodine-stabilized Nd:YAG directly microwave that controls spacing. Additional measurements established at 633 and 778 nm using same confirm accepted uncertainties for these standards.
Three distinct techniques exist for distributing an ultrastable frequency reference over optical fibers. For the distribution of a microwave reference, amplitude-modulated continuous wave (cw) laser can be used. Over kilometer-scale lengths this approach provides instability at 1 s approximately 3 x 10(-14) without stabilization fiber-induced noise and with active cancellation. An transferred by directly transmitting stabilized cw fiber then disseminated to other regions using comb. This 2...
Optical and radio frequency standards located in JILA National Institute of Standards Technology (NIST) laboratories have been connected through a 3.45-km optical fiber link. An standard based on an iodine-stabilized Nd:YAG laser at 1064 nm (with instability ∼4×10-14 1 s) has transferred from to NIST simultaneously measured both laboratories. In parallel, hydrogen maser-based ∼2.4×10-13 is JILA. Comparison between these made possible by the use femtosecond combs The degradation rf that are...
With its direct correspondence to electronic structure, angle-resolved photoemission spectroscopy (ARPES) is a ubiquitous tool for the study of solids. When extended temporal domain, time-resolved (TR)-ARPES offers potential move beyond equilibrium properties, exploring both unoccupied structure as well dynamical response under ultrafast perturbation. Historically, extreme ultraviolet sources employing high-order harmonic generation (HHG) have required compromises that make it challenging...
We demonstrate quantum interference control of injected photocurrents in a semiconductor using the phase stabilized pulse train from mode-locked Ti:sapphire laser. Measurement comb offset frequency via this technique results signal-to-noise ratio 40 dB (10 Hz resolution bandwidth), enabling solid-state detection carrier-envelope shifts oscillator.
We demonstrate a significant improvement in signal-to-noise ratio coherent anti-Stokes Raman scattering (CARS) spectroscopy/microscopy, using two highly synchronized picosecond Ti:sapphire lasers. A temporal jitter between the pulse trains from independent commercial lasers is reduced few picoseconds to ~21 fs , maintained over several hours. The tight synchronization brings fluctuation of CARS signal down shot-noise limit, leading enhanced vibrational images living cells and polymer beads.
We demonstrate a mode-locked, erbium-doped fiber laser with its repetition frequency synchronized to second via an intracavity electro-optic modulator (EOM). With servo control from the EOM (bandwidth approximately 230 kHz) and slower speed piezoelectric transducer (resonance at 20 kHz), we stabilization of in-loop rms timing jitter 10 fs, integrated over bandwidth 1 Hz 100 kHz. This represents what is our knowledge first time has been introduced inside mode-locked cavity for fast action...
Abstract Cuprate high- T c superconductors are known for their intertwined interactions and the coexistence of competing orders. Uncovering experimental signatures these is often first step in understanding complex relations. A typical spectroscopic signature interaction between a discrete mode continuum excitations Fano resonance/interference, characterized by asymmetric light-scattering amplitude as function electromagnetic driving frequency. In this study, we report new type resonance...
Monolithic colliding pulse mode-locking (CPM) in semiconductor lasers is compared with self (SCPM) through a large signal dynamic computer model which incorporates most of the significant features lasers. These include gain saturation, spontaneous emission, gain-frequency relation, and line-width enhancement factor. This new replicates many published experimental results also gives additional insight into internal operation device. In particular, saturation combined standing waves created by...
We obtain direct stabilization of the carrier-envelope phase for a standard x-folded geometry, octave-spanning, Ti:sapphire laser. The in-loop accumulated error is 0.175 rad (1.65 mHz to 102 kHz). Intracavity continuum generation, which responsible octave bandwidth, characterized through measurement beam parameters.
In spintronics, the two main approaches to actively control electrons' spin involve static magnetic or electric fields. An alternative avenue relies on use of optical fields generate currents, which can bolster spin-device performance, allowing for faster and more efficient logic. To date, research has mainly focused injection currents through photogalvanic effect, little is known about direct intrinsic spin-splitting. explore manipulation a material's properties, we consider Rashba effect....
Transfer of a high-stability and ultralow-jitter timing signal through fiber network via mode-locked laser is demonstrated. With active cancellation the fiber-transmission noise, fractional instability for transfer radio-frequency 6.9- (4.5-) km round-trip installed (laboratory-based) below 9(7)×10−15 τ−1∕2 an averaging time τ⩾1 s, limited by noise floor frequency-counting system. The reduces rms jitter, integrated over bandwidth from 1 Hz to 100 kHz, 37 (20) fs network, representing what...
We show that a stretched-pulse mode-locked fiber laser produces welldefined frequency comb, providing compact source of combs and allowing comb-based optical metrology to be extended into the 1.55 microm region. This is achieved by comparing doubled output Ti:Sapphire laser, after two lasers are synchronized. The offset comb found highly sensitive pump power, which enables implementation feedback loop control frequency. resulting RMS jitter heterodyne beat signal 355 kHz (0.5 Hz - 102 BW)...
We now appreciate the fruit of decades development in independent fields ultrasensitive spectroscopy, ultrastable lasers, ultrafast and nonlinear optics. But a new feature past two or three years is explosion interconnectedness between these fields, opening remarkable unexpected progress each, due to advances other fields. For brevity, we here focus mainly on possibilities field optical frequency measurement.
The carrier-envelope phase of the pulse train emitted by a 10-fs mode-locked laser has been stabilized such that coherence is maintained for at least 150 s (measurement limited). time was measured independently feedback loop.
We report on the synchronization of two commercial picosecond Ti:sapphire lasers with unprecedented low temporal jitter between pulse trains. Pulse is reduced from a few picoseconds to 20 fs stability several hours. The technology enabling tight reviewed in this article. demonstrate usefulness scheme by applying technique coherent anti-Stokes Raman scattering (CARS) microscopy. It shown that CARS images can be acquired significant improvement signal-to-noise ratio. This level performance...
Coherent anti-Stokes Raman scattering (CARS) microscopy is demonstrated to be a powerful imaging technique with chemical specificity for studying chemically amplified polymer photoresists. Samples of poly(tert-butyloxycarbonyloxystyrene) (PTBOCST) resist imprinted by interferometric lithography pattern lines/spaces 400 nm/400 nm and 200 nm/200 were used test CARS capabilities. Chemical contrast in the image obtained probing carbonyl stretching vibration tert-butoxyl group PTBOCST. The...
The frequency-domain mode comb of a Ti:sapphire femtosecond laser centered at 350 THz is broadened to 150 (full width -30 dBc) by self-phase modulation in single-mode optical fiber. By phase locking continuous-wave lasers elements the near 1064 and 778 nm, we measure 104-THz frequency gap between these two with relative uncertainty 2.7×10-11 1 s.
A technique is presented for generating optical frequency combs centered at arbitrary wavelengths by use of cross-phase modulation (XPM) between a femtosecond pulse train and cw laser beam copropagating these signals through an fiber. We report results from this method to place 90-MHz comb on iodine-stabilized Nd:YAG 1064 nm frequency-doubled Nd:YVO4 532 nm. XPM verified be the comb-generating process, width measured compared with theory. The spacing source, measurement demonstrated.
We demonstrate a new experimental approach for flexible femtosecond pulse generation in the mid-IR by use of difference-frequency from two tightly synchronized Ti:sapphire lasers. The resultant train can be easily tuned, with an adjustable repetition frequency up to 100 MHz, energy approximately 1.5 x 10(-13) J, and intensity noise similar that Ti:sapphire. Rapid switching wavelength programmable amplitude modulation are achieved precision setting time delay between original pulses.
We report the implementation and operation of novel superhigh-reflectivity negative-dispersion dielectric mirrors for use in tunable ultrafast laser systems. The mirror structure is divided into two distinct regions: an underlying quarter-wavelength stack overlying section consisting only a few layers forming simple multiple Gires–Tournois interferometers. example that we present was designed from 800 to 900 nm has near-constant group-delay dispersion -40 fs2 peak reflectivity greater than...
We report the precise transfer of radio-frequency signals by use pulse repetition frequency mode-locked laser sources at 1.5 microm transmitting through a fiber network. The passive instability 6.9-km is below 3 x 10(-14) 1 s, which comparable with optical carrier-frequency narrow-linewidth cw laser. measurement system 7 10(-15) s. It noted that pulsed mode operation offers almost an order-of-magnitude improvement in stability s over sinusoidal amplitude modulation on carrier.