Optics-microwave entanglement and state teleportation mediated by a cavity magnomechanical system

Kavli Affiliate: Ya Blanter | Summary:Generating usable output-entanglement in continuous variable systems can serve as a viable resource for improving applications in quantum information science. In this work, we show how to generate steady-state output-entanglement in a two-stage conversion setup between optical and microwave photon which employs resonantly coupled magnetic and mechanical excitations, as proposed […]


Continue.. Optics-microwave entanglement and state teleportation mediated by a cavity magnomechanical system

Optics-microwave entanglement and state teleportation mediated by a cavity magnomechanical system

Kavli Affiliate: Ya Blanter | Summary:Generating usable output-entanglement in continuous variable systems can serve as a viable resource for improving applications in quantum information science. In this work, we show how to generate steady-state output-entanglement in a two-stage conversion setup between optical and microwave photon which employs resonantly coupled magnetic and mechanical excitations, as proposed […]


Continue.. Optics-microwave entanglement and state teleportation mediated by a cavity magnomechanical system

Magnon polaritons in a van der Waals ferromagnet coupled to a superconducting resonator

Kavli Affiliate: Herre Van Der Zant | Summary:Achieving magnon-photon hybridization in the microwave regime is essential for integrating magnetic excitations with superconducting circuits. While this has been extensively demonstrated in bulk magnetic systems, realizing it in two-dimensional van der Waals materials remains challenging due to their reduced magnetic volume and increased dissipation. Here, magnon-photon hybridization […]


Continue.. Magnon polaritons in a van der Waals ferromagnet coupled to a superconducting resonator

Coherence limitations of a Fourier-engineered $cos(2varphi)$ transmon qubit

Kavli Affiliate: Christian Andersen | Summary: Intrinsically protected superconducting qubits are a promising route toward enhancing coherence times and advancing hardware towards applications in quantum computing. The $cos(2varphi)$ qubit achieves protection against qubit relaxation by allowing only the coherent tunneling of pairs of Cooper pairs, resulting in Cooper-pair parity symmetry and thereby suppressing charge-induced errors. […]


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g-tensor Optimization in Ge/SiGe Quantum Dots

Kavli Affiliate: Eliska Greplova | Summary:Planar germanium heterostructures hosting hole-spin qubits are among the leading platforms for scalable semiconductor-based quantum computing. Yet, device performance is hindered by significant quantum dot variability, which leads to uncertainty in qubit energy levels and random orientations of the spin quantization axis. Tailored control of the g-tensor offers a strategy […]


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Large quantum dot energy level shifts in anomalous photon-assisted tunneling

Kavli Affiliate: Menno Veldhorst | Summary:Orbital energy splittings are important quantum dot parameters for the operation of hole spin qubits. They are known to depend on the lateral confinement of the quantum dots. However, when changing top, plunger gate voltages, which are the typical control parameter for qubit applications, such energy splitting changes are typically […]


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Magnomechanical Coupling in Suspended 2D van der Waals Ferromagnets

Kavli Affiliate: Herre Van Der Zant | Summary:Magnomechanical systems provide a promising route for exploring coherent hybrid magnon-phonon interactions and hybrid information processing, but their realization has so far been limited by weak magnon-phonon coupling in conventional bulk platforms. We show that a suspended membrane of a two-dimensional van der Waals ferromagnet with in-plane magnetization […]


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Non-magnetic floating phases in frustrated Haldane chains with a single-ion anisotropy

Kavli Affiliate: Natalia Chepiga | Summary:We investigate the effect of a single-ion anisotropy on the bilinear-biquadratic spin-1 J1-J2 chain, focusing on the quantum phase transitions out of the trimerized phase. Using large-scale density matrix renormalization group simulations, we uncover a rich phase diagram comprising five gapped phases and, remarkably, two critical floating phases. These incommensurate […]


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Singlet-triplet oscillations in multivalley Si double quantum dots

Kavli Affiliate: Giordano Scappucci | Summary:Charge separation from the $(4,0)$ to the $(3,1)$ state in a Si/SiGe double quantum dot is commonly used for initialization of spin qubits and Pauli-spin-blockade readout. It was used in recent experiments involving creation of the $(3,1)$ singlet, and subsequent shuttling of one of the electrons. We present a theoretical […]


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Strain engineering of Andreev spin qubits in Germanium

Kavli Affiliate: Anton Akhmerov | Summary:Planar germanium heterostructures are promising hosts for hybrid quantum devices due to their compatibility with superconductors, low material disorder, and relaxed fabrication constraints. Also, the potentially low density of nuclear spins and strong spin-orbit interaction make germanium attractive for coherent spin physics. However, recent microwave spectroscopy experiments were unable to […]


Continue.. Strain engineering of Andreev spin qubits in Germanium