The control and measurement of local non-equilibrium configurations is utmost importance in applications on energy harvesting, thermoelectrics heat management nano-electronics. This challenging task can be achieved with the help various probes, prominent examples including superconducting or quantum dot based tunnel junctions, classical resistors, Raman thermography. Beyond time-averaged properties, valuable information also gained from spontaneous fluctuations current (noise). From these...

Recent topological band theory distinguishes electronic insulators with respect to various symmetries and invariants, most commonly, the time reversal symmetry ${Z}_{2}$ invariant. The interface of two topologically distinct hosts a unique class states---the helical states, which shortcut gapped bulk exhibit spin-momentum locking. magic so far elusive property electrons, known as protection, prevents them from coherent backscattering long underlying is preserved. Here we present an...

We investigate transport and shot noise in lateral N-TI-S contacts, where N is a normal metal, TI Bi-based three dimensional topological insulator (3D TI), S an s-type superconductor. In state, the devices are elastic diffusive regime, as demonstrated by nearly universal value of Fano factor $F_{\rm N}\approx1/3$ magnetic field reference contact. absence field, we identify Andreev reflection (AR) which gives rise to effective charge doubling measurements. Surprisingly, AR}\approx0.22\pm0.02$...

We apply noise thermometry to characterize charge and thermoelectric transport in single InAs nanowires (NWs) at a bath temperature of 4.2 K. Shot measurements identify elastic diffusive our NWs with negligible electron–phonon interaction. This enables us set up measurement the diffusion thermopower. Unlike previous approaches, we make use primary electronic calibrate thermal bias across NW. In particular, this contact heating scheme, which is much more efficient creating as compared...

Nonlocal quasiparticle transport in normal-superconductor-normal (NSN) hybrid structures probes sub-gap states the proximity region and is especially attractive context of Majorana research. Conductance measurement provides only partial information about nonlocal response composed from both electron-like hole-like excitations. In this work, we show how a shot noise delivers missing puzzle piece NSN InAs nanowire-based devices. We demonstrate that trivial superconducting phase practically...

Mesoscopic superconductivity deals with various quasiparticle excitation modes, only one of them -- the charge-mode being directly accessible for conductance measurements due to imbalance in populations quasi-electron and quasihole branches. Other modes carrying heat or even spin, valley etc. currents populate branches equally are charge-neutral, which makes much harder control. This noticeable gap experimental studies mesoscopic non-equilibrium can be filled by going beyond conventional DC...

Shot noise measurements are widely used for the characterization of nonequilibrium configurations in electronic conductors. The recently introduced quantum tomography approach was implemented studies wavefunctions few-electron excitations created by periodic voltage pulses phase-coherent ballistic conductors based on high-quality GaAs two-dimensional electron gas. Still relying manifestation Fermi correlations noise, we focus simpler and more general beneficial local energy distribution (ED)...

We study nonlinear transport and nonequilibrium current noise in quasiclassical point contacts (PCs) defined a low-density, high-quality two-dimensional electron system GaAs. At not too high bias voltages $V$ across the PC, temperature is determined by Joule heat power almost independent on PC resistance that can be associated with self-heating of electronic system. This commonly accepted scenario breaks down at increasing $V$, where we observe extra accompanied strong decrease PC's...

We critically address the recent experiment [Science 382, 907 (2023)] on nonequilibrium transport and noise in a strange metal YbRh2Si2 patterned into nanowire shape. In long device, resistivity, differential resistance current data seem to be consistent allowing us extract electron-phonon coupling temperature dependence of scattering length. The obtained values can reconciled with experimental for short device only assuming significant contact resistance. discuss its possible origin as due...

We investigate the impact of transport current on superconducting order parameter in islands full-shell epitaxial Al-InAs nanowires. Depending device layout, suppression superconductivity occurs three fundamentally different ways-by a critical case reservoirs and by voltage or Joule power normal reservoirs. In latter case, collapse state depends ratio dwell time electron-phonon relaxation quasiparticles island. For low resistive high coupling to reservoirs, respectively, relaxation-free...

We investigate lateral p-n junctions, electrostatically defined in 14 nm-wide HgTe-based quantum wells (QWs) with inverted band structure. The junctions resistances are close to $h/2e^2$, consistent some previous experiments on 8-10 nm QWs, and the current-voltage characteristics highly linear, indicating transport via ballistic helical edge states. Shot noise measurements performed order further verify underlying mechanism. discuss role of unknown inelastic relaxation rates leads channels...

We analyze the benefits and shortcomings of a thermal control in nanoscale electronic conductors by means contact heating scheme.Ideally, this straightforward approach allows one to apply known bias across nanostructures directly through metallic leads, avoiding conventional substrate intermediation.We show, using average noise thermometry local sensing technique InAs nanowire-based devices, that constriction on SiO 2 acts like diffusive conductor with negligible electronphonon relaxation...

Theoretically, the helical edge states of two-dimensional topological insulators are protected from coherent backscattering due to nonmagnetic disorder provided electron interactions not too strong. Experimentally, edges typically do demonstrate systematic and robust quantization, but at same time little is known about sub-Kelvin temperature behavior. Here, we report surprising localization in an 8-nm HgTe quantum well zero magnetic field millikelvin temperatures. Additionally,...

The recent paper [Science 382, 907 (2023)] reports on the measurements of shot noise in heavy fermion strange metal YbRh2Si2 patterned into nanowire shape. authors claim that observed suppression can not be attributed to electron-phonon energy relaxation a standard Fermi liquid model but rather indicates failure quasiparticle concept. In this comment, we discuss inconsistency resistivity extracted from devices different length which may turn out crucial analysis due possible contribution...

We critically address the recent experiment by L. Chen et al. [Science 382 , 907 (2023)] on nonequilibrium transport and noise in a strange metal YbRh 2 Si patterned into nanowire shape. In long device, resistivity, differential resistance current data seem to be consistent allowing us extract electron–phonon coupling temperature dependence of scattering length. The obtained values can reconciled with experimental for short device only assuming significant contact resistance. discuss its...

We perform transport and noise measurements for device consisting of a thin NbSe$_2$ flake laid onto the predefined gold electrodes covered with hBN flake. In shot NbSe$_2$/Au tunnel junction (TJ), we identify Andreev reflection regime by demonstrating effective charge doubling. Further, creating temperature gradient across TJ measuring its delta-$T$ in normal state, extract electron-phonon scattering length $T$-dependence. The results absence magnetic field when is superconducting are...

For the three-terminal NSN device with single-mode normal terminals and without Coulomb blockade, we propose interpretation of charge transfer process, which allows us to consistently characterize operation as that a Cooper pair splitter in terms scattering matrix elements well measurable quantities. The obtained explicit expression for splitting probability notably contains two-particle interference term not available from conductance measurements. We show does necessarily rely on...

In this work we provide a step-by-step description of the technique for manufacturing various van der Waals heterostructures. First, discuss procedure to obtain monolayer and few-layer flakes from layered materials, in particular graphite hexagonal boron nitride. Next, consider different approaches assembly depending on required final device. Further, describe detail making ohmic contacts give parameters plasma chemistry metal deposition. We observe field effect transport measurements but...

We investigate the impact of transport current on superconducting order parameter in islands full-shell epitaxial Al-InAs nanowires. Depending a device layout, suppression superconductivity occurs three fundamentally different ways -- by critical case reservoirs and voltage or Joule power normal reservoirs. In latter case, collapse state depends ratio dwell time electron-phonon relaxation quasiparticles island. For low resistive high coupling to reservoirs, respectively, relaxation-free...