Semiconducting molybdenum disulfphide has emerged as an attractive material for novel nanoscale optoelectronic devices due to its reduced dimensionality and large direct bandgap. Since require electron-hole generation/recombination, it is important be able fabricate ambipolar transistors investigate charge transport both in the conduction band valence band. Although n-type transistor operation single-layer few-layer MoS2 with gold source drain contacts was recently demonstrated, been elusive...

We report measurements of mm-wavelength radiation from two-dimensional arrays underdamped Josephson junctions. All our samples emit coherently in a novel synchronized state, which is triggered by resonance the array structure. Measurements detected power as function number $N$ active junctions show threshold, suggesting population inversion. Above scales with ${N}^{2}$ up to an size bigger than free-space wavelength. The highest measured conversion efficiency dc ac about 17%. Our data are...

We report an experimental method that clearly determines the sensing mechanism of carbon-nanotube field effect transistors. The nanotube/electrode contacts are covered with a thick and long passivation layer hinders their exposure to chemicals in controlled fashion, leaving only midsection nanotube exposed. In case nitrogen dioxide, considerably delayed response is fully consistent diffusion gas through layer. results indicate dioxide detection due changes at interfaces between electrodes...

The transport characteristics of graphene devices with low n- or p-type carrier density (∼1010–1011 cm-2), fabricated using a new process that results in minimal organic surface residues, are reported. molecular doping responsible for the densities is initiated by aqua regia. resulting exhibit highly developed ν = 2 quantized Hall resistance plateaus at magnetic field strengths less than 4 T. As service to our authors and readers, this journal provides supporting information supplied...

Atomically thin transition metal dichalcogenides (TMDs) are ideal candidates for ultrathin optoelectronics that is flexible and semitransparent. Photodetectors based on TMDs show remarkable performance, with responsivity detectivity higher than 10^3 A/W 10^12 Jones, respectively, but they plagued by response times as slow several tens of seconds. Although it well established gas adsorbates such water oxygen create charge traps significantly increase both the time, underlying mechanism still...

We study field-effect transistors made of single- and double-walled carbon nanotube networks for applications as memory devices. The transfer characteristics the exhibit a reproducible hysteresis which enables their use nano-sized cells with operations faster than 10 ms, endurance longer + 4 cycles charge retention few hours in air. propose water enhanced trapping at SiO2/air interface close to nanotubes dominant mechanism storage. show that storage can be improved by limiting exposure device

Three-terminal devices with conduction channels formed by quasi-metallic carbon nanotubes (CNTs) are shown to operate as nanotube-based field-effect transistors under strong magnetic fields. The off-state conductance of the varies exponentially flux intensity. We extract CNT chirality well characteristics Schottky barriers at metal−nanotube contacts from temperature-dependent magnetoconductance measurements.

We study memory devices consisting of single-walled carbon nanotube transistors with charge storage at the SiO2/nanotube interface. show that this type device is robust, withstanding over 105 operating cycles, a current drive capability up to 10−6 A 20 mV drain bias, thus competing state-of-the-art Si-devices. find performance depends on temperature and pressure, while both endurance data retention are improved in vacuum.

Two-dimensional materials such as graphene and transition metal dichalcogenides (TMDs) are ideal candidates to create ultra-thin electronics suitable for flexible substrates. Although optoelectronic devices based on TMDs have demonstrated remarkable performance, scalability is still a significant issue. Most created using techniques that not mass production, mechanical exfoliation of monolayer flakes patterning by electron-beam lithography. Here we show large-area MoS2 grown chemical vapor...

Terahertz technology has recently emerged as a highly sought-after and versatile scientific tool in many fields, including medical imaging, security screening, wireless communication. However, progress been hindered by the lack of sources detectors this frequency range, thereby known terahertz gap. Here, we show that carbon nanotube quantum dots coupled to antennas are extremely sensitive, broad-band, with spectral resolution. Their response is due photon-assisted single-electron tunneling...

We present experimental and theoretical results showing that the distributed electromagnetic environment of a Josephson junction array can cause junctions in to synchronize. Based on our model, we find an external load is not necessary for synchronization. Also, show high-frequency performance be significantly better than single isolated junction.

The temperature dependence of $1∕f$ noise in individual semiconducting carbon nanotube (CNT) field-effect transistors is used to estimate the distribution activation energies fluctuators $D(E)$ responsible for noise. shows a rise at low energy with no characteristic scale, and broad peak $\ensuremath{\sim}0.4\phantom{\rule{0.3em}{0ex}}\mathrm{eV}$. peak, majority room temperature, cannot be due electronic excitations, carrier number fluctuations, or structural fluctuations CNT, likely...

Abstract Graphene is an ideal material for hot-electron bolometers due to its low heat capacity and weak electron-phonon coupling. Nanostructuring graphene with quantum-dot constrictions yields detectors of electromagnetic radiation extraordinarily high intrinsic responsivity, higher than 1×10 9 V W −1 at 3 K. The sensing mechanism bolometric in nature: the quantum confinement gap causes a strong dependence electrical resistance on electron temperature. Here, we show that this does not...

Light-induced phenomena in materials can exhibit exotic behavior that extends beyond equilibrium properties, offering new avenues for understanding and controlling electronic phases. So far, non-equilibrium solids have been predominantly explored using femtosecond laser pulses, which generate transient, ultra-fast dynamics. Here, we investigate the steady regime graphene induced by a continuous-wave (CW) mid-infrared laser. Our transport measurements reveal signatures of long-lived Floquet...

We have measured the complex ac magnetic susceptibility of unshunted Josephson-junction arrays as a function temperature $T$, amplitude excitation field ${h}_{\mathrm{ac}}$, and external ${H}_{\mathrm{dc}}$. For small ${h}_{\mathrm{ac}}$ Meissner screening occurs. larger however, is reentrant in $T$. This reentrance not thermodynamic but dynamic arises from paramagnetic contribution multijunction loops. result gives an alternative explanation effect observed granular superconductors....

We demonstrate that indium tin oxide nanowires (ITO NWs) and cationic polymer-modified ITO NWs configured in a network format can be used as high performing UV/vis photodetectors. The photovoltage response of is much higher than similarly constructed devices made from oxide, zinc nanostructures. NW mesh-based exhibit substantial (31-100 mV under illumination with 1.14 mW 543 nm laser) photocurrent (225-325 μA at 3 V). time the fast rise 20-30 μs decay 1.5-3.7 ms when probed 355 pulsed laser....

The paramagnetic Meissner effect (PME) measured in high $T_{C}$ granular superconductors has been attributed to the presence of $\pi$-junctions between grains. Here we present measurements complex AC magnetic susceptibility from two-dimensional arrays conventional (non $\pi$) Nb/Al/AlOx/Nb Josephson junctions. We as a function temperature $T$, amplitude excitation field, $h_{AC}$, and external $H_{DC}$. experiments show strong contribution multi-junction loops, which manifests itself...

We have successfully fabricated devices with isolated single-walled carbon nanotubes (SWNTs) using exclusively standard i-line (365 nm) photolithography. Catalyst islands were patterned an SU-8-photoresist-based process. This method provides well-defined islands, down to 1 µm in size. The are clearly visible optical microscope and used as alignment marks for of subsequent layers. SWNTs grown by chemical vapour deposition (CVD). Contacts the

Van Hove singularities (VHSs) are a hallmark of reduced dimensionality, leading to divergent density states in one and two dimensions predictions new electronic properties when the Fermi energy is close these divergences. In carbon nanotubes, VHSs mark onset subbands. They elusive standard transport characterization measurements because they do not typically appear as notable features therefore their effect on nanotube conductance largely unexplored. Here we report nanotubes where clearly...