Christopher Baker

Christopher Baker
The University of Queensland | UQ · School of Mathematics and Physics

PhD in physics, Université Paris Diderot

About

71
Publications
11,034
Reads
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1,208
Citations
Additional affiliations
July 2019 - July 2020
The University of Queensland
Position
  • Fellow
November 2014 - present
The University of Queensland
Position
  • PostDoc Position
Description
  • http://researchers.uq.edu.au/researcher/11198
November 2013 - October 2014
Paris Diderot University
Position
  • PostDoc Position
Education
September 2009 - October 2013
Paris Diderot University
Field of study
  • Physics

Publications

Publications (71)
Article
Full-text available
We analyze the magnitude of the radiation pressure and electrostrictive stresses exerted by light confined inside GaAs semiconductor WGM optomechanical disk resonators, through analytical and numerical means, and find the electrostrictive force to be of prime importance. We investigate the geometric and photoelastic optomechanical coupling resultin...
Article
Full-text available
Following vortices around When stirred, superfluids react by creating quantized vortices. Studying the dynamics of these vortices, especially in the strongly interacting regime, is technically challenging. Sachkou et al. developed a technique for the nondestructive tracking of vortices in thin films of superfluid helium-4. Their system contained a...
Article
Full-text available
Brillouin scattering has applications ranging from signal processing1,2, sensing³ and microscopy⁴ to quantum information⁵ and fundamental science6,7. Most of these applications rely on the electrostrictive interaction between light and phonons3,7,8. Here we show that in liquids optically induced surface deformations can provide an alternative and f...
Preprint
Full-text available
Nanomechanical computers promise robust, low energy information processing. However, to date, electronics have generally been required to interconnect gates, while no scalable, purely nanomechanical approach to computing has been achieved. Here, we demonstrate a nanomechanical logic gate in a scalable architecture. Our gate uses the bistability of...
Preprint
Full-text available
When confined within an optical cavity, light can exert strong radiation pressure forces. Combined with dynamical backaction, this enables important processes such as laser cooling, and applications ranging from precision sensors to quantum memories and interfaces. However, the magnitude of radiation pressure forces is constrained by the energy mis...
Article
Full-text available
We demonstrate a hermetically sealed packaging system for integrated photonic devices at cryogenic temperatures with plug-and-play functionality. This approach provides the ability to encapsulate a controlled amount of gas into the optical package allowing helium to be used as a heat-exchange gas to thermalize photonic devices, or condensed into a...
Chapter
In this chapter, we provide an overview of Brillouin scattering from a quantum fluid, superfluid helium. Its vanishing viscosity at low temperatures, combined with other extreme material properties, provides a choice set of characteristics for Brillouin interactions. We describe the basics of superfluid helium and its optoacoustic interactions, bot...
Preprint
We demonstrate a hermetically sealed packaging system for integrated photonic devices at cryogenic temperatures with plug-and-play functionality. This approach provides the ability to encapsulate a controlled amount of gas into the optical package allowing helium to be used as a heat-exchange gas to thermalize photonic devices, or condensed into a...
Chapter
Cavity optomechanics and Brillouin scattering have historically developed as separate fields of study, focused on distinct optoacoustic interaction effects, and realized in different physical platforms. These gaps are now closing rapidly, as researchers embrace the fundamental similarities between the two fields. Both fields study the three-wave mi...
Article
Full-text available
In semiconductor nano-optomechanical resonators, several forms of light-matter interaction can enrich the canonical radiation pressure coupling of light and mechanical motion and give rise to new dynamical regimes. Here, we observe an electro-optomechanical modulation instability in a gallium arsenide disk resonator. The regime is evidenced by the...
Article
Full-text available
Nanomechanical circuits for transverse acoustic waves promise to enable new approaches to computing, precision biochemical sensing, and many other applications. However, progress is hampered by the lack of precise control of the coupling between nanomechanical elements. Here, we demonstrate virtual-phonon coupling between transverse mechanical elem...
Article
Full-text available
We show that highly confined superfluid films are extremely nonlinear mechanical resonators, offering the prospect to realize a mechanical qubit. Specifically, we consider third-sound surface waves, with nonlinearities introduced by the van der Waals interaction with the substrate. Confining these waves to a disk, we derive analytic expressions for...
Preprint
Full-text available
Nanomechanical circuits for transverse acoustic waves promise to enable new approaches to computing, precision biochemical sensing and many other applications. However, progress is hampered by the lack of precise control of the coupling between nanomechanical elements. Here, we demonstrate virtual-phonon coupling between transverse mechanical eleme...
Article
Full-text available
The ability to tune the wavelength of light emission on a silicon chip is important for scalable photonic networks, distributed photonic sensor networks, and next generation computer architectures. Here we demonstrate light emission in a chip-scale optomechanical device, with wide tunablity provided by a combination of radiation pressure and photot...
Preprint
Full-text available
The ability to tune the wavelength of light emission on a silicon chip is important for scalable photonic networks, distributed photonic sensor networks and next generation computer architectures. Here we demonstrate light emission in a chip-scale optomechanical device, with wide tunablity provided by radiation pressure. To achieve this, we develop...
Article
Full-text available
Brillouin systems operating in the quantum regime have recently been identified as a valuable tool for quantum information technologies and fundamental science. However, reaching the quantum regime is extraordinarily challenging, owing to the stringent requirements of combining low thermal occupation with low optical and mechanical dissipation, and...
Preprint
Full-text available
Brillouin systems operating in the quantum regime have recently been identified as a valuable tool for quantum information technologies and fundamental science. However, reaching the quantum regime is extraordinarily challenging, owing to the stringent requirements of combining low thermal occupation with low optical and mechanical dissipation, and...
Preprint
Full-text available
We show that highly confined superfluid films are extremely nonlinear mechanical resonators, offering the prospect to realize a mechanical qubit. Specifically, we consider third-sound surface waves, with nonlinearities introduced by the van der Waals interaction with the substrate. Confining these waves to a disk, we derive analytic expressions for...
Preprint
Full-text available
Brillouin scattering has applications ranging from signal processing, sensing and microscopy, to quantum information and fundamental science. Most of these applications rely on the electrostrictive interaction between light and phonons. Here we show that in liquids optically-induced surface deformations can provide an alternative and far stronger i...
Article
Full-text available
We demonstrate a single-mode acoustic waveguide that enables robust propagation of mechanical waves. The waveguide is a highly stressed silicon-nitride membrane that supports the propagation of out-of-plane modes. In direct analogy to rectangular microwave waveguides, there exists a band of frequencies over which only the fundamental mode is allowe...
Article
Full-text available
Vorticity in two-dimensional superfluids is subject to intense research efforts due to its role in quantum turbulence, dissipation and the BKT phase transition. Interaction of sound and vortices is of broad importance in Bose–Einstein condensates and superfluid helium. However, both the modelling of the vortex flow field and of its interaction with...
Preprint
We demonstrate a single-mode phononic waveguide that enables robust propagation of mechanical waves. The waveguide is a highly-stressed silicon nitride membrane that supports the propagation of out-of-plane modes. In direct analogy to rectangular microwave waveguides, there exists a band of frequencies over which only the fundamental mode is allowe...
Preprint
Full-text available
Two-dimensional superfluidity and quantum turbulence are directly connected to the microscopic dynamics of quantized vortices. However, surface effects have prevented direct observations of coherent vortex dynamics in strongly-interacting two-dimensional systems. Here, we overcome this challenge by confining a two-dimensional droplet of superfluid...
Preprint
Full-text available
Two-dimensional superfluidity and quantum turbulence are directly connected to the microscopic dynamics of quantized vortices. However, surface effects have prevented direct observations of coherent vortex dynamics in strongly-interacting two-dimensional systems. Here, we overcome this challenge by confining a two-dimensional droplet of superfluid...
Preprint
Full-text available
Vorticity in two-dimensional superfluids is subject to intense research efforts due to its role in quantum turbulence, dissipation and the BKT phase transition. Interaction of sound and vortices is of broad importance in Bose-Einstein condensates and superfluid helium [1-4]. However, both the modelling of the vortex flow field and of its interactio...
Conference Paper
We report free-spectral-range tuning in a high-quality on-chip microcavity requiring less than 15 V and 1 nW of power to maintain optical resonance with an arbitrary frequency: an important component for achieving reconfigurable photonic circuits.
Article
Full-text available
Reconfigurable photonic circuits have applications ranging from next-generation computer architectures to quantum networks, coherent radar and optical metamaterials. Here, we demonstrate an on-chip high quality microcavity with resonances that can be electrically tuned across a full free spectral range (FSR). FSR tuning allows resonance with any so...
Article
Full-text available
Reconfigurable photonic circuits have applications ranging from next-generation computer architectures to quantum networks, coherent radar and optical metamaterials. Here, we demonstrate an on-chip high quality microcavity with resonances that can be electrically tuned across a full free spectral range (FSR). FSR tuning allows resonance with any so...
Article
Full-text available
The original version of this Article omitted the fourth author, Sara Ducci from Matériaux et Phénomènes Quantiques, Université Paris Diderot, CNRS UMR 7162, Sorbonne Paris-Cité, 10 rue Alice Domon et Léonie Duquet, Paris 75013, France. This mistake has been corrected in both the HTML and PDF versions of the Article.
Preprint
Full-text available
Reconfigurable photonic circuits have applications ranging from next-generation computer architectures to quantum networks, coherent radar and optical metamaterials. However, complete reconfigurability is only currently practical on millimetre-scale device footprints. Here, we overcome this barrier by developing an on-chip high quality microcavity...
Conference Paper
Using superfluid optomechanical system, here we show both that radiation pressure can greatly deform superfluid film, increasing its local thickness by over a factor of 2, and that this generates new sound modes within the film locally, that are confined by the optical mode and interact strongly with it. This demonstrates a new form of dynamical ba...
Article
Full-text available
Quantum physics ultimately constrains how well sensors of position, speed and acceleration can perform. A hybrid quantum system that avoids these constraints could give rise to improved sensor technologies. See Letter p.191
Article
Full-text available
The techniques of cavity optomechanics have enabled significant achievements in precision sensing, including the detection of gravitational waves and the cooling of mechanical systems to their quantum ground state. Recently, the inherent non-linearity in the optomechanical interaction has been harnessed to explore synchronization effects, including...
Article
Full-text available
Photonic lattices of mutually interacting indistinguishable cavities represent a cornerstone of collective phenomena in optics and could become important in advanced sensing or communication devices. The disorder induced by fabrication technologies has so far hindered the development of such resonant cavity architectures, while post-fabrication tun...
Data
Supplementary Figures, Supplementary Notes and Supplementary References
Data
Real-time video of the experimental resonant PEC tuning of the whispering gallery doublet resonance of a single GaAs disk resonator.
Data
Video illustration of spectral self-alignment of three distinct photonic resonators by resonant PEC tuning.
Conference Paper
Full-text available
Electro-optomechanical systems are a platform for exploring rich physics such as frequency conversion and synchronization. Here we demonstrate the first case of inertial injection locking in a radiation pressure driven electro-optomechanical system.
Article
Full-text available
Excitations in superfluid helium represent attractive mechanical degrees of freedom for cavity optomechanics schemes. Here we numerically and analytically investigate the properties of optomechanical resonators formed by thin films of superfluid ⁴He covering micrometer-scale whispering gallery mode cavities. We predict that through proper optimizat...
Article
Single-mode optical nanofibres are a central component of a broad range of applications and emerging technologies. Their fabrication has been extensively studied over the past decade, but imaging of the final sub-micrometre products has been restricted to destructive or low-precision techniques. Here we demonstrate an optical scattering-based scann...
Article
Full-text available
Collective phenomena emerging from non-linear interactions between multiple oscillators, such as synchronization and frequency locking, find applications in a wide variety of fields. Optomechanical resonators, which are intrinsically non-linear, combine the scientific assets of mechanical devices with the possibility of long distance controlled int...
Article
Full-text available
Excitations in superfluid helium represent attractive mechanical degrees of freedom for cavity optomechanics schemes. Here we numerically and analytically investigate the properties of optomechanical resonators formed by thin films of superfluid $^4$He covering micrometer-scale whispering gallery mode cavities. We predict that through proper optimi...
Patent
Full-text available
The invention concerns a method for tuning at a targeted resonance wavelength at least one micro and/or nanophotonic resonator, the resonator having dimensions defining resonance wavelength of said resonator, the resonator being immersed in a fluid containing ions so that the resonator is surrounded by said fluid, wherein the method comprises a ste...
Article
Full-text available
Single-mode optical nanofibres are a central component of a broad range of applications and emerging technologies. Their fabrication has been extensively studied over the past decade, but imaging of the final sub-micrometre products has been restricted to destructive or low-precision techniques. Here we demonstrate an optical scattering-based scann...
Article
Full-text available
We report on the design, fabrication and characterization of silica microtoroid based cavity opto-electromechanical systems (COEMS). Electrodes patterned onto the microtoroid resonators allow for rapid capacitive tuning of the optical whispering gallery mode resonances while maintaining their ultrahigh quality factor, enabling applications such as...
Conference Paper
We demonstrate that miniature optomechanical disk resonators can operate in liquids as ultrafast and ultrasensitive densimeters, viscometers and mass sensors. We develop numerical and analytical models that describe the fluid-structure interactions at play around these GHz mechanical devices. We test them experimentally by immersing disks of varyin...
Article
Full-text available
In cavity optomechanics, radiation pressure and photothermal forces are widely utilized to cool and control micromechanical motion, with applications ranging from precision sensing and quantum information to fundamental science. Here, we realize an alternative approach to optical forcing based on superfluid flow and evaporation in response to optic...
Article
Full-text available
We present a simple method to tune optical micro- and nanocavities with picometer precision in the resonant wavelength, corresponding to an effective sub atomic monolayer control of the cavity dimension. This is obtained through resonant photo-electrochemical etching, with in-situ monitoring of the optical spectrum. We employ this technique to spec...
Article
Full-text available
Whispering gallery modes in GaAs disk resonators reach half a million of optical quality factor. These high Qs remain still well below the ultimate design limit set by bending losses. Here we investigate the origin of residual optical dissipation in these devices. A Transmission Electron Microscope analysis is combined with an improved Volume Curre...
Article
Full-text available
Superfluidity is an emergent quantum phenomenon which arises due to strong interactions between elementary excitations in liquid helium. These excitations have been probed with great success using techniques such as neutron and light scattering. However measurements to-date have been limited, quite generally, to average properties of bulk superflui...
Article
Full-text available
Here we present laser based readout and control of the Brownian motion of a thin film of superfluid helium formed around an optical microresonator. Detuned laser driving allows photothermal induced laser cooling and heating, while amplitude modulation probes the nonlinear Duffing interaction.
Article
Full-text available
Vibrating nano- and micromechanical resonators have been the subject of research aiming at ultrasensitive mass sensors for mass spectrometry, chemical analysis and biomedical diagnosis. Unfortunately, their merits diminish dramatically in liquids due to dissipative mechanisms like viscosity and acoustic losses. A push towards faster and lighter min...
Article
Full-text available
We experimentally demonstrate the controlled enhancement of the mechanical quality factor Q of gallium arsenide disk optomechanical resonators. Disks vibrating at 1.3 GHz with a mechanical shield integrated in their pedestal show a Q improvement by a factor 10–16. The structure is modeled numerically and different modes of vibration are observed, w...
Thesis
Full-text available
This thesis work focuses on the design, fabrication and measurement of Gallium Arsenide (GaAs) nano-optomechanical disk resonators. These disks are both GHz frequency mechanical resonators, and high Q (>10^5) optical whispering gallery mode resonators. By confining optical and mechanical energy on a sub-µm^3 volume, they enable extremely large opto...