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Single-electron tunneling in InP nanowires

De Franceschi, S. (author), Van Dam, J.A. (author), Bakkers, E.P.A.M. (author), Feiner, L.F. (author), Gurevich, L. (author), Kouwenhoven, P. (author)

We report on the fabrication and electrical characterization of field-effect devices based on wire-shaped InP crystals grown from Au catalyst particles by a vapor–liquid–solid process. Our InP wires are n-type doped with diameters in the 40–55-nm range and lengths of several micrometers. After being deposited on an oxidized Si substrate, wires...

journal article 2003

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Spontaneous emission control of single quantum dots in bottom-up nanowire waveguides

Bulgarini, G. (author), Reimer, M.E. (author), Zehender, T. (author), Hocevar, M. (author), Bakkers, E.P.A.M. (author), Kouwenhoven, L.P. (author), Zwiller, V. (author)

Nanowire waveguides with controlled shape are promising for engineering the collection efficiency of quantum light sources. We investigate the exciton lifetime in individual InAsP quantum dots, perfectly positioned on-axis of InP nanowire waveguides. We demonstrate control over the quantum dot spontaneous emission by varying the nanowire...

journal article 2012

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Photon- and phonon-assisted tunneling in the three-dimensional charge stability diagram of a triple quantum dot array

Braakman, F.R. (author), Barthelemy, P. (author), Reichl, C. (author), Wegscheider, W. (author), Vandersypen, L.M.K. (author)

We report both photon- and phonon-assisted tunneling transitions in a linear array of three quantum dots, which can only be understood by considering the full three-dimensionality of the charge stability diagram. Such tunneling transitions potentially contribute to leakage of qubits defined in this system. A detailed understanding of these...

journal article 2013

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Diameter-dependent conductance of InAs nanowires

Scheffler, M. (author), Nadj-Perge, S. (author), Kouwenhoven, L.P. (author), Borgström, M.T. (author), Bakkers, E.P.A.M. (author)

Electrical conductance through InAs nanowires is relevant for electronic applications as well as for fundamental quantum experiments. Here, we employ nominally undoped, slightly tapered InAs nanowires to study the diameter dependence of their conductance. By contacting multiple sections of each wire, we can study the diameter dependence within...

journal article 2009

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The Einstein relation in quantum wires of III-V, ternary, and quaternary materials in the presence of light waves: Simplified theory, relative comparison, and suggestion for experimental determination

Ghatak, K.P. (author), Bhattacharya, S. (author), Bhowmik, S. (author), Benedictus, R. (author), Choudhury, S. (author)

We study the Einstein relation for the diffusivity to mobility ratio (DMR) in quantum wires (QWs) of III-V, ternary, and quaternary materials in the presence of light waves, whose unperturbed energy band structures are defined by the three band model of Kane. It has been found, taking n-InAs, n-InSb, n-Hg1?xCdxTe, n-In1?xGaxAsyP1?y lattice...

journal article 2008

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Electro-optic detection of subwavelength terahertz spot sizes in the near field of a metal tip

Van der Valk, N.C.J. (author), Planken, P.C.M. (author)

We report on a method to obtain a subwavelength resolution in terahertz time-domain imaging. In our method, a sharp copper tip is used to locally distort and concentrate the THz electric field. The distorted electric field, present mainly in the near field of the tip, is electro-optically measured in an (100) oriented GaP crystal. By raster...

journal article 2002

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Tuning single GaAs quantum dots in resonance with a rubidium vapor

Akopian, N. (author), Perinetti, U. (author), Wang, L. (author), Rastelli, A. (author), Schmidt, O.G. (author), Zwiller, V. (author)

We study single GaAs quantum dots with optical transitions that can be brought into resonance with the widely used D2 transitions of rubidium atoms. We achieve resonance by Zeeman or Stark shifting the quantum dot levels. We discuss an energy stabilization scheme based on the absorption of quantum dot photoluminescence in a rubidium vapor. This...

journal article 2010

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Transmission measurement of the photonic band gap of GaN photonic crystal slabs

Caro, J. (author), Roeling, E.M. (author), Rong, B. (author), Nguyen, H.M. (author), Van der Drift, E.W.J.M. (author), Rogge, S. (author), Karouta, F. (author), Van der Heijden, R.W. (author), Salemink, H.W.M. (author)

A high-contrast-ratio (30 dB) photonic band gap in the near-infrared transmission of hole-type GaN two-dimensional photonic crystals (PhCs) is reported. These crystals are deeply etched in a 650 nm thick GaN layer grown on sapphire. A comparison of the measured spectrum with finite difference time domain simulations gives quantitative agreement...

journal article 2008

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Location of lanthanide impurity levels in the III-V semiconductor GaN

Dorenbos, P. (author), Van der Kolk, E. (author)

Knowledge from lanthanide spectroscopy on wide band gap (6–10?eV) inorganic compounds is used to understand and predict optical and electronic properties of the lanthanides in the III-V semiconductor GaN. For the first time the location of the 4fn ground state energy of each divalent and trivalent lanthanide ion relative to the valence and...

journal article 2006

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Position controlled nanowires for infrared single photon emission

Dorenbos, S.N. (author), Sasakura, H. (author), Van Kouwen, M.P. (author), Akopian, N. (author), Adachi, S. (author), Namekata, N. (author), Jo, M. (author), Motohisa, J. (author), Kobayashi, Y. (author), Tomioka, K. (author), Fukui, T. (author), Inoue, S. (author), Kumano, H. (author), Natarajan, C.M. (author), Hadfield, R.H. (author), Zijlstra, T. (author), Klapwijk, T.M. (author), Zwiller, V. (author), Suemune, I. (author)

We report the experimental demonstration of single-photon and cascaded photon pair emission in the infrared, originating from a single InAsP quantum dot embedded in a standing InP nanowire. A regular array of nanowires is fabricated by epitaxial growth on an electron-beam patterned substrate. Photoluminescence spectra taken on single quantum...

journal article 2010

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Surround-gated vertical nanowire quantum dots

Van Weert, M.H.M. (author), Den Heijer, M. (author), Van Kouwen, M.P. (author), Algra, R.E. (author), Bakkers, E.P.A.M. (author), Kouwenhoven, L.P. (author), Zwiller, V. (author)

We report voltage dependent photoluminescence experiments on single indium arsenide phosphide (InAsP) quantum dots embedded in vertical surround-gated indium phosphide (InP) nanowires. We show that by tuning the gate voltage, we can access different quantum dot charge states. We study the anisotropic exchange splitting by polarization analysis,...

journal article 2010

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Phase locking of a 3.4 THz third-order distributed feedback quantum cascade laser using a room-temperature superlattice harmonic mixer

Hayton, D.J. (author), Khudchenko, A. (author), Pavelyev, D.G. (author), Hovenier, J.N. (author), Baryshev, A. (author), Gao, J.R. (author), Kao, T.Y. (author), Hu, Q. (author), Reno, J.L. (author), Vaks, V. (author)

We report on the phase locking of a 3.4 THz third-order distributed feedback quantum cascade laser (QCL) using a room temperature GaAs/AlAs superlattice diode as both a frequency multiplier and an internal harmonic mixer. A signal-to-noise level of 60?dB is observed in the intermediate frequency signal between the 18th harmonic of a 190.7?GHz...

journal article 2013

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Single quantum dot nanowire photodetectors

Van Kouwen, M.P. (author), Van Weert, M.H.M. (author), Reimer, M.E. (author), Akopian, N. (author), Perinetti, U. (author), Algra, R.E. (author), Bakkers, E.P.A.M. (author), Kouwenhoven, L.P. (author), Zwiller, V. (author)

We report InP nanowire photodetectors with a single InAsP quantum dot as light absorbing element. With excitation above the InP band gap, the nanowire photodetectors are efficient (quantum efficiency of 4%). Under resonant excitation of the quantum dot, the photocurrent amplitude depends on the linear polarization direction of the incident light...

journal article 2010

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Excited-state spectroscopy on a nearly closed quantum dot via charge detection

Elzerman, J.M. (author), Hanson, R. (author), Willems van Beveren, L.H. (author), Vandersypen, L.M.K. (author), Kouwenhoven, L.P. (author)

We demonstrate a method for measuring the discrete energy spectrum of a quantum dot connected very weakly to a single lead. A train of voltage pulses applied to a metal gate induces tunneling of electrons between the quantum dot and a reservoir. The effective tunnel rate depends on the number and nature of the energy levels in the dot made...

journal article 2004

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Optical polarization properties of a nanowire quantum dot probed along perpendicular orientations

Bugarini, G. (author), Reimer, M.E. (author), Zwiller, V. (author)

We report on the optical properties of single quantum dots in nanowires probed along orthogonal directions. We address the same quantum dot from either the nanowire side or along the nanowire axis via reflection on a micro-prism. The collected photoluminescence intensity from nanowires lying on a substrate is improved 3-fold using the prism as...

journal article 2012

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Strong modification of the reflection from birefringent layers of semiconductor nanowires by nanoshells

Diedenhofen, S.L. (author), Algra, R.E. (author), Bakkers, E.P.A.M. (author), Gómez Rivas, J. (author)

The propagation of light in layers of vertically aligned nanowires is determined by their unique and extreme optical properties. Depending on the nanowire filling fraction and their diameter, layers of nanowires form strongly birefringent media. This large birefringence gives rise to sharp angle dependent peaks in polarized reflection. We...

journal article 2011

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Comparative study of Cl2, Cl2/O2, and Cl2/N2 inductively coupled plasma processes for etching of high-aspect-ratio photonic-crystal holes in InP

Carlström, C.F. (author), Van der Heijden, R. (author), Andriesse, M.S.P. (author), Karouta, F. (author), Van der Heijden, R.W. (author), Van der Drift, E.W.J.M. (author), Salemink, H.W.M. (author)

An extensive investigation has been performed on inductively coupled plasma etching of InP. An important motivation for this work is the fabrication of high-aspect-ratio holes for photonic crystals. The essential chemistry is based on Cl2 with the addition of N2 or O2 for sidewall passivation. The influence of different process parameters such...

journal article 2008

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Wavelength-sized cavities in high aspect InP/InGaAsP/InP photonic crystals

Kicken, H.H.J.E. (author), Barbu, I. (author), Van der Heijden, R.W. (author), Karouta, F. (author), Nötzel, R. (author), Van der Drift, E. (author), Salemink, H.W.M. (author)

The photonic properties of two classes of wavelength-sized cavities are reported for deeply etched InP/InGaAsP/InP planar photonic crystals. The high aspect, deeply etched structures are studied as potential building blocks for nonmembrane type photonic devices in standard InP photonic integrated circuits. The first class consists of cavities of...

journal article 2009

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Thermoelectric power in carbon nanotubes and quantum wires of nonlinear optical, optoelectronic, and related materials under strong magnetic field: Simplified theory and relative comparison

Ghatak, K.P. (author), Bhattacharya, S. (author), Bhowmik, S. (author), Benedictus, R. (author), Choudhury, S. (author)

We study thermoelectric power under strong magnetic field (TPM) in carbon nanotubes (CNTs) and quantum wires (QWs) of nonlinear optical, optoelectronic, and related materials. The corresponding results for QWs of III-V, ternary, and quaternary compounds form a special case of our generalized analysis. The TPM has also been investigated in QWs of...

journal article 2008

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Beam and phase distributions of a terahertz quantum cascade wire laser

Cui, M. (author), Hovenier, J.N. (author), Ren, Y. (author), Vercruyssen, N. (author), Gao, J.R. (author), Kao, T.Y. (author), Hu, Q. (author), Reno, J.L. (author)

We report on both measurements and simulations of the beam profile and wavefront of a single-mode, 3.5?THz quantum cascade wire laser, incorporating a lateral corrugated metal-metal waveguide, 3rd-order distributed feedback grating. The intrinsic wavefront was measured by using a Hartmann wavefront sensor (HWS) without any optical components...

journal article 2013