A5000702751- Mechanical and Optical Resonators
- Quantum and electron transport phenomena
- Semiconductor Quantum Structures and Devices
- Advancements in Semiconductor Devices and Circuit Design
- Photonic and Optical Devices
- Semiconductor materials and devices
- Advanced MEMS and NEMS Technologies
- Acoustic Wave Resonator Technologies
- Quantum Information and Cryptography
- Quantum optics and atomic interactions
- Radio Frequency Integrated Circuit Design
- Nanowire Synthesis and Applications
- Gyrotron and Vacuum Electronics Research
- Silicon Nanostructures and Photoluminescence
- Microwave Engineering and Waveguides
- Aerodynamics and Fluid Dynamics Research
- Physics of Superconductivity and Magnetism
- Electrowetting and Microfluidic Technologies
- Ferroelectric and Piezoelectric Materials
- Air Traffic Management and Optimization
- Integrated Circuits and Semiconductor Failure Analysis
- Random lasers and scattering media
- Metal and Thin Film Mechanics
- Quantum, superfluid, helium dynamics
- Force Microscopy Techniques and Applications
Paul Drude Institute for Solid State Electronics
2017-2023
Forschungsverbund Berlin
2018-2023
Delft University of Technology
2015-2020
Dartmouth College
2011-2014
University of Wisconsin–Madison
2012
Abstract In cavity optomechanics, light is used to control mechanical motion. A central goal of the field achieving single-photon strong coupling, which would enable creation quantum superposition states Reaching this limit requires significant improvements in optomechanical coupling and coherence. Here we introduce an architecture consisting a silicon nitride membrane coupled three-dimensional superconducting microwave cavity. Exploiting their large quality factors, achieve cooperativity...
Abstract Surface acoustic waves (SAWs) strongly modulate the shallow electric potential in piezoelectric materials. In semiconductor heterostructures such as GaAs/AlGaAs, SAWs can thus be employed to transfer individual electrons between distant quantum dots. This mechanism makes SAW technologies a promising candidate convey information through circuit of logic gates. Here we present two essential building blocks SAW-driven circuit. First, implement directional coupler allowing partition...
We study the mechanical dissipation of fundamental mode millimeter-sized, high quality-factor (Q) metalized silicon nitride membranes at temperatures down to 14 mK using a three-dimensional optomechanical cavity. Below 200 mK, high-Q modes show diverging increase Q with decreasing temperature, reaching Q=1.27×108 an order magnitude higher than that reported before. The ultra-low makes highly attractive for optomechanics in quantum regime, as well other applications such microwave optical...
Abstract Telecommunication of the next generation demands filters that can operate in 10 GHz range with sufficient bandwidths. For surface-acoustic-wave (SAW) devices this prerequisite translates into high sound velocities and piezoelectric couplings. Wurtzite AlN on diamond, which exploits strong piezoelectricity very SAW velocity has been considered a promising platform. A significant boost (up to factor 4) response be obtained by alloying Sc. Here, main challenge lies synthesis...
We report a robust process for fabrication of surface-gated Si/SiGe quantum dots (QDs) with an integrated superconducting single-electron transistor (S-SET) charge sensor. A combination deep mesa etch and AlOx backfill is used to reduce gate leakage. After the leakage current suppressed, Coulomb oscillations QD current-voltage characteristics S-SET are observed at temperature 0.3 K. Coupling confirmed by using perform sensing state.
Microwave optomechanical circuits have been demonstrated in the past years to be extremely powerfool tools for both, exploring fundamental physics of macroscopic mechanical oscillators as well being promising candidates novel on-chip quantum limited microwave devices. In most experiments so far, oscillator is either used a passive device element and its displacement detected using superconducting cavity or manipulated by intracavity fields. Here, we explore possibility directly...
We report the operation of a radio frequency superconducting single-electron transistor (rf-SSET) as charge sensor for single and double Si/SiGe quantum dots (QDs). Real-time electron tunneling events are observed from reflected signal rf-SSET with sensitivity 4×10−6 e/Hz, which demonstrates fast detection time few tens microseconds. Measurements power used to map out stability diagram dot.
We report on a technique for applying DC bias in 3D microwave cavity. achieve this by isolating the two halves of cavity with dielectric and directly using them as electrodes. As proof concept, we embed variable capacitance diode tune resonant frequency voltage, demonstrating incorporation into no measurable change its quality factor at room temperature. also characterize architecture millikelvin temperatures show that split design maintains Qi ∼ 8.8 × 105, making it promising future quantum...
We report on the electrical generation of surface acoustic waves (SAWs) doped semiconductor substrates. This is implemented by using interdigital transducers (IDTs) placed piezoelectric ZnO films sputtered onto evaporated thin metal layers. Two material systems are investigated, namely ZnO/Au/GaAs and ZnO/Ni/InP. The rf-field applied to transducer electrically screened highly conductive film underneath without any extra ohmic losses. As a result, absorption mobile carriers in lossy region...
We experimentally investigate dissipation in mechanical resonators made of a disordered superconducting thin film Molybdenum-Rhenium(MoRe) alloy. By electrostatically driving the drum with resonant AC voltage, we detect its motion using microwave cavity. From temperature dependence resonance frequencies and quality factors, find evidence for non-resonant, mechanically active two-level systems (TLSs) limiting factor at low temperature. In addition, observe strong suppression large amplitudes,...
We report on the selective excitation of single impurity-bound exciton states in a GaAs double quantum well (DQW). The structure consists two wells (QWs) coupled by thin tunnel barrier. DQW is subject to transverse electric field create spatially indirect inter-QW excitons with electrons and holes located different QWs. show that presence intra-QW charged (trions) blocks carrier tunneling across barrier form excitons, thus opening gap their emission spectrum. This behavior attributed low...
Quantum communication networks require on-chip transfer and manipulation of single particles as well their interconversion to photons for long-range information exchange. Flying excitons propelled by GHz surface acoustic waves (SAWs) are outstanding messengers fulfill these requirements. Here, we demonstrate the exciton centers consisting individual bound shallow impurity embedded in a semiconductor quantum well. Time-resolved photoluminescence studies show that emission intensity energy...
We report measurements consistent with the valley Kondo effect in Si/SiGe quantum dots, evidenced by peaks conductance versus source-drain voltage that show strong temperature dependence. The unusual behavior a magnetic field we interpret as arising from degree of freedom. interplay and Zeeman splittings is suggested presence side peaks, revealing zero-field splitting between 0.28 to 0.34 meV. A zero-bias peak for nonzero field, phenomenon nonconservation tunneling, observed two samples.
An important prerequisite for quantum communication networks is the transfer and manipulation of single particles on a chip as well their interconversion to photons long-range information exchange. GHz acoustic waves are versatile tools implementation these functionalities in hybrid systems. In particular, flying excitons propelled by surface (SAWs) can potentially satisfy this prerequisite. article, we review recent works application SAWs realize semiconductor-based Most importantly, have...
Manipulating mechanical waves at gigahertz frequencies can lead to next-generation communication technologies, but designing wave-controlling devices requires high-resolution and fast-scanning mapping of acoustic fields. The authors introduce the use atomic force microscopy characterize phononic crystals frequency, showing vibration with tens-of-nanometer resolution symmetry-dependent scattering. This study sets baseline for advanced operations like hyperspectral filtering, beam steering, or...
We report a technique for applying dc bias in 3d microwave cavity. This is achieved by isolating the two halves of cavity with dielectric and directly using them as electrodes. By embedding variable capacitance diode cavity, we tune resonant frequency voltage at room temperature, demonstrating introduction into without compromising its high quality factor.