Resonant tunneling of electrons through a single self-assembled InAs quantum dot probed via a novel overlayed quantum dot electrode

Kamiya, Itaru; Tanaka, Ichiro; Tada, Yutaka; Azuma, Makoto; Uno, Kazuyuki; Sakaki, H.

doi:10.1016/j.jcrysgro.2004.12.117

Cited by 4 publications

(4 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Since micron-scale electrodes were used in the experiments on the micronscale diodes, this result suggests that the bias voltage applied to our nano-scale QD-electrode is not fully used across the device region. Same effect was also observed when electron resonant tunneling via single InAs QDs shallowly embedded in a GaAs Schottky barrier was measured using InAs QD-electrodes [8].…”

Section: Resultssupporting

confidence: 57%

“…In order to investigate electron tunneling through a single InAs QD without ambiguities, we fabricated nanoscale GaAs Schottky diodes with surface InAs QDs and embedded ones in the Schottky barrier, where surface QDs were vertically aligned with embedded ones and used as nano-scale electrodes, and the conductance change attributted to electron resonant tunneling was clearly observed in I-V characteristics at ~ 120 K [8]. However, it was difficult to observe such conductance change at room temperature because considerable background current still remained.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Resonant tunneling of electrons through single self‐assembled InAs quantum dot at room temperature studied with conductive AFM tip

Tanaka

Tada

Nakatani

et al. 2008

Phys. Status Solidi (c)

Self Cite

View full text Add to dashboard Cite

Resonant tunneling of electrons through a quantum level in a self‐assembled InAs quantum dot (QD) has been measured by conductive atomic force microscopy (AFM) at room temperature. InAs QDs are embedded in a 3.4 nm‐thick AlAs layer, and capped with 8.3 nm‐thick GaAs layer on which surface InAs QDs are deposited as nano‐scale electrodes. Bringing the conductive AFM tip on the surface InAs QD which should be vertically aligned with a buried QD, a bias voltage is applied to the sample, and a current flowing via the buried QD is measured. Negative differential resistance attributed to electron resonant tunnelling through a quantized energy level in the buried QD is observed in the current‐voltage characteristics. The voltage loss by nano‐scale electrode and the dependence of resonance voltage on the size of the surface QD‐electrodes are discussed. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

show abstract

Section: Resultssupporting

confidence: 57%

Section: Introductionmentioning

confidence: 99%

Resonant tunneling of electrons through single self‐assembled InAs quantum dot at room temperature studied with conductive AFM tip

Tanaka

Tada

Nakatani

et al. 2008

Phys. Status Solidi (c)

Self Cite

View full text Add to dashboard Cite

show abstract

“…Recent examples are InAs quantum dots (QDs), used in, e.g., lasers [1] and all-optical switches [2] operating around 1.5 µm, and resonant tunnelling structures [3]. Typically, such QD devices consist of selfassembled InAs islands buried in a barrier material with a higher band gap, such as InP, GaAs, or InGaAsP.…”

Section: Introductionmentioning

confidence: 99%

Modified self-assembly of InAs islands acting as stressors for strain-induced InGaAs(P)/InP quantum dots

Sormunen

Riikonen²,

Mattila³

et al. 2005

Nanotechnology

View full text Add to dashboard Cite

We report modified self-assembly of InAs islands acting as stressors for strain-induced InGaAs(P) quantum dots (SIQDs). The quantum dots are fabricated by growing InAs islands on top of a near-surface InGaAs(P)/InP quantum well (QW). The compressively strained QW affects the size and density of the InAs islands, as compared to islands grown on a plain InP buffer. By adjusting the growth conditions, the height of the InAs stressors is tuned from 15 to 30 nm while the areal density varies around 10 9 cm −2. The confinement of carriers in the SIQDs is characterized by low-temperature photoluminescence. Increasing the size of the InAs stressor is shown to enhance the depth of the lateral confinement potential and reduce the level splitting of excited QD states. However, the small inhomogeneous broadening of the SIQD transitions, as narrow as 11 meV, shows no correlation with the height dispersion of the stressor islands.

show abstract

“…However, we have shown that electronic properties of single InAs QDs self-assembled on GaAs substrates can be obtained using contact-mode AFM with conductive probe, and that the measurements are rather straight forward since the probe is in direct contact with the dots. [10][11][12][13] Furthermore, we applied the same technique to single CdSe colloidal QDs, and their current-voltage (I-V) characteristics were measured even at room temperature. 14,15) In this study, we prepared submonolayer-thick QD films where isolated dots existed on atomically flat surfaces for single dot AFM measurements.…”

mentioning

confidence: 99%

Improved Height Measurement of Single CdSe Colloidal Quantum Dots by Contact-Mode Atomic Force Microscopy Using Carbon Nano-Tube Tips; for the Investigation of Current-Voltage Characteristics

Tanaka

Kajimoto

Uno

et al. 2005

Jpn. J. Appl. Phys.

View full text Add to dashboard Cite

We have investigated the distribution of measured heights of single CdSe colloidal quantum dots (QDs) by contact-mode atomic force microscopy. The dot heights measured with metal-coated Si tips, with which large adhesive force is measured between the tip and sample, are much smaller than that expected from optical absorption. This discrepancy could be due to the dot position fluctuation that occurs when the tip is in contact with the dot because the height distribution of the QDs covered with very thin SiO2 layer is in agreement with the optical measurement. On the other hand, when conductive carbon nano-tube (CNT) tips are used, the adhesive force is reduced significantly, and the measured dot heights become close to the expected value. Thus, the measurement of QD height is greatly improved in accuracy with CNT tips. As a result, the current flowing through the QD can be measured, and conductance changes attributed to electron resonant tunneling through the QD are observed.

show abstract

Resonant tunneling of electrons through a single self-assembled InAs quantum dot probed via a novel overlayed quantum dot electrode

Cited by 4 publications

References 24 publications

Resonant tunneling of electrons through single self‐assembled InAs quantum dot at room temperature studied with conductive AFM tip

Resonant tunneling of electrons through single self‐assembled InAs quantum dot at room temperature studied with conductive AFM tip

Modified self-assembly of InAs islands acting as stressors for strain-induced InGaAs(P)/InP quantum dots

Improved Height Measurement of Single CdSe Colloidal Quantum Dots by Contact-Mode Atomic Force Microscopy Using Carbon Nano-Tube Tips; for the Investigation of Current-Voltage Characteristics

Contact Info

Product

Resources

About