Demonstration of a nanophotonic switching operation by optical near-field energy transfer

Kawazoe, Tadashi; Kobayashi, Kiyoshi; Sangu, Suguru; Ohtsu, Motoichi

doi:10.1063/1.1571977

Cited by 140 publications

(56 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…24,25 As a representative device, a nanophotonic switch can be realized by controlling the dipole forbidden optical energy transfer among resonant energy levels in nanometer-scale QD via an optical near field. 26 Since the switching dynamics was already confirmed using CuCl quantum cubes, 26 the success of near-field PL and absorption measurement of isolated SQWs described above is a promising step toward designing a nanophotonic switch and related devices.…”

Section: -mentioning

confidence: 99%

Near-field measurement of spectral anisotropy and optical absorption of isolated ZnO nanorod single-quantum-well structures

Yatsui

Ohtsu

Yoo

et al. 2005

Applied Physics Letters

Self Cite

View full text Add to dashboard Cite

We report low-temperature near-field spectroscopy of isolated ZnO / ZnMgO single-quantum-well structures ͑SQWs͒ on the end of ZnO nanorod to define their potential for nanophotonics. First, absorption spectra of isolated ZnO / ZnMgO nanorod SQWs with the Stokes shift as small as 3 meV and very sharp photoluminescent peaks indicate that the nanorod SQWs are of very high optical quality. Furthermore, we performed polarization spectroscopy of isolated ZnO SQWs, and observed valence-band anisotropy of ZnO SQWs in photoluminescence spectra directly. Since the exciton in a quantum structure is an ideal two-level system with long coherence times, our results provide criteria for designing nanophotonic devices. © 2005 American Institute of Physics. ͓DOI: 10.1063/1.1990247͔ ZnO nanocrystallites are a promising material for realizing nanometer-scale photonic devices, 1 i.e., nanophotonic devices, at room temperature, owing to their large exciton binding energy 2-4 and large oscillator strength. 5 Furthermore, the recent demonstration of semiconductor nanorod quantumwell structures enables us to fabricate nanometer-scale electronic and photonic devices on single nanorods. [6][7][8][9] Recently, ZnO / ZnMgO nanorod heterostructures were fabricated and the quantum confinement effect even from the singlequantum-well structures ͑SQWs͒ was observed. 10 Near-field spectroscopy has made a remarkable contribution to investigations of the optical properties in nanocrystallite, 11 and has resulted in the observation of nanometer-scale optical images, such as the local density of exciton states. 12 However, reports on semiconductor quantum structure are limited to naturally formed quantum dots ͑QDs͒. 12-14 Here we report low-temperature near-field spectroscopy of artificially fabricated ZnO SQWs on the end of a ZnO nanorod.ZnO / ZnMgO SQWs were fabricated on the ends of ZnO stems with a mean diameter of 40 nm and a length of 1 m using catalyst-free metalorganic vapor phase epitxy, in which the ZnO nanorods were grown vertically from a sapphire ͑0001͒ substrate in the c orientation. 10,15 The Mg concentration in the ZnMgO layers averaged 20 at. %. Two samples were prepared for this study: their ZnO well layer thickness L w , were 2.5 and 3.75 nm, while the thicknesses of the ZnMgO bottom and top barrier layers in the SQWs were fixed at 60 and 18 nm, respectively. After growing the ZnO / ZnMgO nanorod SQWs, they were dispersed so that they were laid down on a flat sapphire substrate to isolate them from each other ͓Fig. 1͑a͔͒.The far-field photoluminescence ͑PL͒ spectra were obtained using a He-Cd laser ͑ = 325 nm͒ before dispersion of the ZnO / ZnMgO nanorod SQWs. The emission signal was collected with the acromatic lens ͑f =50 mm͒. To confirm that the optical qualities of individual ZnO / ZnMgO SQWs were sufficiently high, we used a collection-mode near-field optical microscope ͑NOM͒ using a He-Cd laser ͑ = 325 nm͒ for excitation, and a UV fiber probe with an aperture diameter of 30 nm. The excitation source was focused on a nanorod ...

show abstract

Section: -mentioning

confidence: 99%

Near-field measurement of spectral anisotropy and optical absorption of isolated ZnO nanorod single-quantum-well structures

Yatsui

Ohtsu

Yoo

et al. 2005

Applied Physics Letters

Self Cite

View full text Add to dashboard Cite

show abstract

“…In view of the drive to scale down electronics components, such a device that operates on the molecular level should prove of considerable interest, particularly when it is scaled up into paired arrays. [13][14][15] Mechanisms for exerting and exploiting control over optical energy flow are only just beginning to receive due attention, [14][15][16][17][18][19][20] and the challenge is to develop devices based on such principles. Our initial analysis has identified a concept that makes it possible to engineer a configuration of optical switches with parallel processing capability, without exhibiting significant cross-talk.…”

Section: Discussionmentioning

confidence: 99%

Near-field propagation in planar nanostructured arrays

Andrews

Crisp

2006

SPIE Proceedings

View full text Add to dashboard Cite

In suitably designed nanoscale systems the ultrafast migration of uv/visible electromagnetic energy, despite its nearfield rather than propagating character, can be made highly directional. At the photon level such energy migration generally takes a multi-step form, with each step signifying the transfer of an electromagnetic quantum between chromophores playing the transient roles of source/donor and detector/acceptor. There is much interest in nanophotonic devices based on such mechanisms, although the excitation transfer is usually subject to losses such as radiative decay, and possible device applications are compromised by a lack of suitable control mechanisms. Until recently it appeared that only by inefficient and kinetically frustrated means, such as chromophore reorientation or movement, could significant control be effected. However in a system constructed to inhibit near-field propagation by geometric configuration, the throughput of laser pulses can facilitate energy transfer through a process of laser-assisted resonant energy transfer. Suitably configuring an arrangement of dipoles, it proves possible to design parallel arrays of optical donors and acceptors such that the transfer of energy from any single donor, to its counterpart in the opposing plane, is switched by throughput laser radiation of an appropriate intensity, frequency and polarization. A detailed appraisal of some possible realizations of this system reveals an intricate interplay of electronic structure, optical frequency and geometric factors. In the drive to miniaturize ultrafast optical switching and interconnect devices, the results suggest a new basis for optically activated transistor action in nanoscale components, with significant parallel processing capability.

show abstract

“…The possibility for efficient generation of local optical fields -which could be used for carrying out optical probing, manipulation and spectroscopic analysis -at the nanometre scale is moved one step closer to reality by the ability to excite NQDs by the Förster transfer of energy from a quantum well. Finally, by using a cascade of energy transfers along a chain of other NQDs -the feasibility of which has already been established 6,7 -the potential functionality of this approach could be extended still further.…”

Section: Light-emitting Devicesmentioning

confidence: 99%

From nano-optics to street lights

Stockman

2004

Nature Mater

View full text Add to dashboard Cite

Demonstration of a nanophotonic switching operation by optical near-field energy transfer

Cited by 140 publications

References 11 publications

Near-field measurement of spectral anisotropy and optical absorption of isolated ZnO nanorod single-quantum-well structures

Near-field measurement of spectral anisotropy and optical absorption of isolated ZnO nanorod single-quantum-well structures

Near-field propagation in planar nanostructured arrays

From nano-optics to street lights

Contact Info

Product

Resources

About