Search arXiv⌕ Search

arXiv · 2609.39435

Giant PhotoMagnetoDiode Effect

Abstract

We report the observation of a photomagnetodiode effect with a giant rectification ratio of 10 at a magnetic field of 0.1 T. The effect consists of a diode-like dependence of the photocurrent on the applied voltage that emerges in an external magnetic field. Such a pronounced nonreciprocity is observed in high-quality VPE-grown GaAs samples at low temperatures at interband photoexcitation. The photoconductivity is invariant upon reversing the polarity of both electric and magnetic fields. Similar behavior with even higher asymmetry ratio is observed in photoluminescence. The findings are well described by the theory of ambipolar drift of carriers in electric and magnetic fields together with fast surface recombination.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

V. L. Korenev, S. A. Tarasenko. 2026-09-30. Giant PhotoMagnetoDiode Effect. https://arxiv.org/abs/2609.39435

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

Tunneling probe-based characterisation of the sp${}^3$ dangling bond on the H-C(100):$2\times1$ surface

The sp${}^3$ dangling bond on the diamond surface plays a critical role in the performance and fabrication of diamond quantum technologies. For the former, the magnetic and electric properties of this defect can impede the performance of quantum sensors and computers. For the latter, the chemical properties of the dangling bond are integral to proposed methods for bottom-up fabrication of scalable diamond quantum devices. In pursuit of high-performance, scalable diamond quantum technology, tunnelling probe-based techniques offer the ability to create and modify the sp${}^3$ dangling bond with atomic-scale precision. However, these capabilities cannot be realised either deterministically or at scale without a means of identifying the sp${}^3$ dangling bond amidst the myriad of other defects on the diamond surface. Consequently, in this work we provide a comprehensive experimental and theoretical framework for STS-based characterisation of the sp${}^3$ defect on the H-terminated (100) diamond surface. This capability provides the foundation for future tunnelling probe studies in the modification of dangling bonds.

cond-mat.mes-hall↗

Damping-dependent thermalization of neighboring nanomechanical resonators below 1 mK

The position noise spectra of six drums on a single chip were measured on a single cooldown below 1.3 kelvin. Cryostat temperatures as low as 0.7 mK were achieved. The temperature dependence of the resonance frequency and linewidth of the drum modes was analyzed in the framework of the tunneling two level system (TLS) model. Departures of the resonance frequency and the position noise power from the expected logarithmic and linear temperature dependences, respectively, were interpreted as indications of thermal decoupling from the cryostat. This previously unexplored measurement configuration revealed that similar neighboring drums on a single chip may be at different temperatures. At the lowest temperatures, some drums exhibited excess damping that decreased with temperature. The magnitude of the excess damping of the drums was correlated with the thermal coupling of their TLS to the cryostat. In the case of one drum, a temporary increase in its damping coincided with a decrease in its mode temperature. The thermalization of the TLS to the cold finger was independent of pump power, pulse tube state and temperature of the pre-cooling stages of the cryostat. These results suggest that thermalization of nanomechanics to the cryostat can be mediated by TLS damping rather than clamping loss and may impact efforts to extend the coherence of mechanical resonators.

cond-mat.mes-hall↗

Symmetry-enabled tunable square-lattice Hubbard models in $Γ$-valley moiré bilayers

Square-lattice moiré systems provide a promising route for quantum simulation of Hubbard physics, yet electrically tunable realizations of the hopping ratio $t'/t$ have so far been limited to specific valley configurations. A natural question is whether the same tunability can be extended to the more broadly occurring $Γ$-valley systems. Here we identify a symmetry-controlled route for realizing electrically tunable square-lattice Hubbard models in $Γ$-valley twisted homobilayers. At small twist angles, an emergent layer-exchange symmetry separates the low-energy states into flat bands localized on two nested square sublattices, suppressing inter-sublattice hopping. An interlayer displacement field breaks this symmetry and induces controllable hybridization between the sublattices, enabling continuous tuning of the $t'/t$ ratio over a wide range while preserving an effective single-band description. We further establish a formal correspondence between $Γ$- and M-valley moiré systems, revealing them as different symmetry limits of a unified framework for tunable square-lattice Hubbard models. Our results uncover a general symmetry principle underlying displacement-field tunability and extend electrically controllable square-lattice Hubbard physics to a broad family of $Γ$-valley materials.

cond-mat.mes-hall↗