Structural Influence of Erbium Centers on Silicon Nanocrystal Phase Transitions

Senter, Robert A.; Pantea, Cristian; Wang, Yuejian; Liu, Haozhe; Żerda, T. W.; Coffer, Jeffery L.

doi:10.1103/physrevlett.93.175502

Cited by 22 publications

(14 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Nonlinear high pressure behaviour of ω was also observed in Ge nanoparticles embedded into SiO 2 matrix [13] (~-0.4 cm -1 /GPa 2 ) and in Ge islands on Si surface [11,12]. Closest analogues (free of matrix) where similar non-linear behaviour was also observed are porous Si [22] and nano-crystalline Si [23].…”

Section: /Gpasupporting

confidence: 50%

Raman study of nano‐crystalline Ge under high pressure

Sapelkin

Karavanskiĭ

Kartopu

et al. 2007

Physica Status Solidi (b)

View full text Add to dashboard Cite

We investigated high pressure behaviour of nano‐crystalline Ge that is free of substrate up to 17 GPa using Raman scattering. Nano‐crystalline Ge has been prepared by stain‐etching of 100 oriented Ge wafer and then lifted off. Electron diffraction measurements revealed that after etching particles retain diamond structure of original mono‐crystalline wafer. The Raman peak corresponding to zone‐center optical phonons mode was found to be shifted at ambient conditions from 300 cm–1 found in c‐Ge to around 280(1) cm–1 in nano‐crystalline Ge. Particle size was estimated from Raman and TEM measurements to be ∼5 nm. We observed no pressure transformation from the diamond to a high pressure phase as expected for bulk Ge (at around 10 GPa) in our Raman measurements. The pressure dependence of the Raman peak position was found to be highly nonlinear with dω /dP = 3.9(1) cm–1/GPa and d2ω /dP2 = –0.14(2) cm–1/GPa2. We discuss the microscopic origins of observed high pressure behavior of nano‐crystalline Ge. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

show abstract

Section: /Gpasupporting

confidence: 50%

Raman study of nano‐crystalline Ge under high pressure

Sapelkin

Karavanskiĭ

Kartopu

et al. 2007

Physica Status Solidi (b)

View full text Add to dashboard Cite

show abstract

“…In order to achieve that, the Si-NC-induced sensitization process of Er emission in SiO 2 has to be thoroughly understood. In the past, Förster (dipole-dipole) mechanism has been proposed in order to explain the energy transfer from Si-NC's to Er 3 [6,7] and different locations of Er in respect to Si-NC have been considered [8,9]. However, in spite of a considerable progress by both modeling and experiment [2,10], many issues still lack sufficient explanation.…”

mentioning

confidence: 99%

Nanosecond Dynamics of the Near-Infrared Photoluminescence of Er-DopedSiO2Sensitized with Si Nanocrystals

Izeddin

Moskalenko²,

In³

et al. 2006

Phys. Rev. Lett.

View full text Add to dashboard Cite

We report on an observation of a fast 1.5 microm photoluminescence band from Er3+ ions embedded in an SiO2 matrix doped with Si nanocrystals, which appears and decays within the first microsecond after the laser excitation pulse. We argue that the fast excitation and quenching are facilitated by Auger processes related to transitions of confined electrons or holes between the space-quantized levels of Si nanocrystals dispersed in SiO2. We show that a great part--about 50%--of all Er dopants is involved in these fast processes and contributes to the submicrosecond emission.

show abstract

“…11 and 12͒ and different locations of Er, with respect to Si NC, have been considered. 13,14 In addition to the relatively slow ͑ s range͒ NC-mediated Er 3+ excitation, a much faster ͑100 ns range͒ and usually more dominating process has also been concluded. 15 Its physical origin has been considered recently 16 and participation of special luminescence centers in erbium excitation has been postulated in particular for low-temperature annealed samples.…”

Section: Introductionmentioning

confidence: 99%

Energy transfer in Er-dopedSiO2sensitized with Si nanocrystals

et al. 2008

View full text Add to dashboard Cite

We present a high-resolution photoluminescence study of Er-doped SiO 2 sensitized with Si nanocrystals ͑Si NCs͒. Emission bands originating from recombination of excitons confined in Si NCs, internal transitions within the 4f-electron core of Er 3+ ions, and a band centered at Ϸ 1200 nm have been identified. Their kinetics were investigated in detail. Based on these measurements, we present a comprehensive model for energy-transfer mechanisms responsible for light generation in this system. A unique picture of energy flow between the two subsystems was developed, yielding truly microscopic information on the sensitization effect and its limitations. In particular, we show that most of the Er 3+ ions available in the system are participating in the energy exchange. The long-standing problem of apparent loss of optical activity in the majority of Er dopants upon sensitization with Si NCs is clarified and assigned to the appearance of a very efficient energy exchange mechanism between Si NCs and Er 3+ ions. Application potential of SiO 2 : Er, sensitized by Si NCs, was discussed in view of the newly acquired microscopic insight.

show abstract

Structural Influence of Erbium Centers on Silicon Nanocrystal Phase Transitions

Cited by 22 publications

References 24 publications

Raman study of nano‐crystalline Ge under high pressure

Raman study of nano‐crystalline Ge under high pressure

Nanosecond Dynamics of the Near-Infrared Photoluminescence of Er-DopedSiO2Sensitized with Si Nanocrystals

Energy transfer in Er-dopedSiO2sensitized with Si nanocrystals

Contact Info

Product

Resources

About