Related papers: Photocurrent in a visible-light graphene photodiod…

We study photodetection in graphene near a local electrostatic gate, which enables active control of the potential landscape and carrier polarity. We find that a strong photoresponse only appears when and where a p-n junction is formed,…

A near-field scanning optical microscope is used to locally induce photocurrent in a graphene transistor with high spatial resolution. By analyzing the spatially resolved photo-response, we find that in the n-type conduction regime a p-n-p…

The photoresponse of graphene at mid-infrared frequencies is of high technological interest and is governed by fundamentally different underlying physics than the photoresponse at visible frequencies, as the energy of the photons and…

Photogalvanic effect (PGE) occurring in noncentrosymmetric materials enables the generation of the open-circuit voltage that is much larger than the bandgap, making it rather attractive in solar cells. However, the magnitude of the PGE…

Advances in manipulating the structure of optical beams enable the study of interaction between structured light and low-dimensional semiconductor systems. We explore the photocurrents in two-dimensional systems excited by such…

Photodetection is a process in which an incident field induces a polarization current in the detector. The interaction of the field with this induced current excites an electron in the detector from a localized bound state to a state in…

The photoexcitation life-cycle from incident photon (and creation of photoexcited electron hole pair) to ultimate extraction of electrical current is a complex multi-physics process spanning across a range of spatio-temporal scales of…

Photocurrent-induced harmonics appear in gases and solids due to tunnel ionization of electrons in strong fields and subsequent acceleration. In contrast to three-step harmonic emission, no return to the parent ions is necessary. Here we…

We study transport properties of graphene-based p-n junctions irradiated by an electromagnetic field (EF). The resonant interaction of propagating quasiparticles with an external monochromatic radiation opens dynamical gaps in their…

The photogalvanic effect is the generation of a second-order direct current by illumination of a non-centrosymmetric material. In this work, we develop a first-principles real-time density matrix (FPDMD) formalism enabling the calculations…

We show theoretically that electromagnetic waves propagating in the transparency region of a non-centrosymmetric medium can induce a dc electric current. The origin of the effect is the Raman scattering of light by free carriers in the…

Nonlinear photocurrent carriers in conjugated polymers, such as polarons, bipolarons and solitons, are considered at low photon energies where a tunnelling process is necessary. We show that polarons usually dominate the photocurrent I due…

Graphene is a promising candidate for the development of detectors of Terahertz (THz) radiation. A well-known detection scheme due to Dyakonov and Shur exploits the confinement of plasma waves in a field-effect transistor (FET), whereby a…

We report a first principles investigation of photocurrent generation by graphene PN junctions. The junctions are formed by either chemically doping with nitrogen and boron atoms, or by controlling gate voltages. Non-equilibrium Green's…

We study the generation of an electromagnetic current in monolayer graphene immersed in a weak perpendicular magnetic field and radiated with linearly polarized monochromatic light. Such a current emits Bremsstrahlung radiation with the…

Finding alternative optoelectronic mechanisms that overcome the limitations of conventional semiconductor devices is paramount for detecting and harvesting low-energy photons. A highly promising approach is to drive a current from the…

Graphene is widely recognized for its ultrafast and broadband photocurrent response, but whether the broadband ultrafast characteristics are preserved at mid-infrared wavelengths with photon energies below the optical phonon energy remains…

Graphene electrodes provide a suitable alternative to metal contacts in molecular conduction nanojunctions. Here, we propose to use graphene electrodes as a platform for effective photon assisted tunneling through molecular conduction…

Optoelectronic measurements of carbon nanotube transistors have shown a wide variety of sensitivites to the incident light. Direct photocurrent processes compete with a number of extrinsic mechanisms. Here we show that visible light…

Strong Coulomb interaction in monolayer semiconductors allows them to host optically active large many-body states, such as the five-particle state, charged biexciton. Strong nonlinear light absorption by the charged biexciton under…