An extreme bandgap AlGaN quantum channel HEMT with AlGaN top and back barriers, grown by MOCVD on a bulk AlN substrate, demonstrated a critical breakdown field of 11.37 MV/cm-higher than the 9.8 MV/cm expected for the channel's AlGaN material. We show that the fraction of this increase is due to the quantization of the 2D electron gas. The polarization field maintains electron quantization in the quantum channel even at low sheet densities, in contrast to conventional HEMT designs. An additional increase in the breakdown field is due to quantum-enabled real space transfer of energetic electrons into high-Al barrier layers in high electric fields. These results show the advantages of the quantum channel design for achieving record-high breakdown voltages and allowing for superior power HEMT devices.
Metasurface with natural static structure limits the development of dynamic metasurface holographic display with rapid response and broadband. Currently, liquid crystal (LC) was integrated onto the metasurface to convert the passive metasuface into an active one. But, majority of LC-assisted active metasurfaces often exhibit trade-offs among degree of freedom (DoF, typically less than 2), information capacity, response speed, and crosstalk.
Room-temperature cavity quantum electrodynamics with molecular materials in optical cavities offers exciting prospects for controlling electronic, nuclear and photonic degrees of freedom for applications in physics, chemistry and materials science. However, achieving strong coupling with molecular ensembles typically requires high molecular densities and substantial electromagnetic-field confinement. These conditions usually involve a significant degree of molecular disorder and a highly structured photonic density of states.
Magnetic microrobot swarms have broad application prospects in human-targeted therapy. However, the automated assembly and actuation of functional large-volume swarms is a challenging topic. Chlorella with self-fluorescence and biodegradability is used in this paper as a template to prepare magnetic Chlorella-based microrobots through magnetron sputtering.
We calculate the two-loop heavy quarkonium Hamiltonian within potential-nonrelativistic-QCD effective field theory in the nonannihilation channel. This calculation represents the first nontrivial step toward determining the N^{4}LO Hamiltonian in the weak coupling regime. The large amount of computation is systematically handled by employing the β expansion, differential equations for master integrals, and adopting a single-step matching procedure, in contrast to the conventional two-step approach.
The dynamics of open quantum systems can be simulated by unraveling it into an ensemble of pure state trajectories undergoing nonunitary monitored evolution, which has recently been shown to undergo measurement-induced entanglement phase transition. Here, we show that, for an arbitrary decoherence channel, one can optimize the unraveling scheme to lower the threshold for entanglement phase transition, thereby enabling efficient classical simulation of the open dynamics for a broader range of decoherence rates. Taking noisy random unitary circuits as a paradigmatic example, we analytically derive the optimum unraveling basis that on average minimizes the threshold.
