Raman microscopy analysis of phase transformation mechanisms in vanadium dioxide

Petrov, Georgi I.; Yakovlev, Vladislav V.; Squier, Jeffrey A.

doi:10.1063/1.1496506

Cited by 166 publications

(100 citation statements)

References 32 publications

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“…• C. Also no evidence of phonon softening near the transition temperature has been found by the temperature dependence of Raman spectra measured with a VO 2 single crystal and a thin film [6]. These results support the electron correlation model of the MIT.…”

supporting

confidence: 77%

Temperature dependence of the first-order metal-insulator transition in VO2 and programmable critical temperature sensor

Kim

Lee

Chae

et al. 2007

Applied Physics Letters

196

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The temperature dependence of the Mott metal-insulator transition (MIT) is studied with a VO2-based two-terminal device. When a constant voltage is applied to the device, an abrupt current jump is observed with temperature. With increasing applied voltages, the transition temperature of the MIT current jump decreases. We find a monoclinic and electronically correlated metal (MCM) phase between the abrupt current jump and the structural phase transition (SPT). After the transition from insulator to metal, a linear increase in current (or conductivity) is shown with temperature until the current becomes a constant maximum value above TSP T ≈68• C. The SPT is confirmed by micro-Raman spectroscopy measurements. Optical microscopy analysis reveals the absence of the local current path in micro scale in the VO2 device. The current uniformly flows throughout the surface of the VO2 film when the MIT occurs. This device can be used as a programmable critical temperature sensor.PACS numbers: 71.27. +a, 71.30.+hThe first-order Mott discontinuous metal-insulator transition (MIT) has been studied as a function of temperature in numerous materials such as Ti 2 O 3 , V 2 O 3 , and VO 2 etc [1]. Almost all have a transition temperature, T MIT , below room temperature except VO 2 which has T MIT ≈68• C. In particular, VO 2 thin films were used for fabrication of two-and three-terminal devices controlled by an electric field [2]. A high-speed Mott switching device using an abrupt current jump as observed in I-V measurements was predicted for manufacturing in the nano-level transistor regime [3,4].Moreover, Raman experiments [5] for a VO 2 film have showed monoclinic-insulator peaks after the film had undergone an electric-field-induced transition from an insulator to a metal. Furthermore, tetragonal-metal peaks have been associated with the structural phase transition (SPT) above 68• C. Also no evidence of phonon softening near the transition temperature has been found by the temperature dependence of Raman spectra measured with a VO 2 single crystal and a thin film [6]. These results support the electron correlation model of the MIT. However, some reports argue that the electric field-induced MIT is due to Joule heating by current and is accompanied by SPT, and that, furthermore, the local current path or current filament formed by the dielectric breakdown [7] can also cause the jump (MIT). The dielectric breakdown was described by depinning and the collective transport of charge carriers above a threshold voltage. Here, we try to elucidate this ambiguity through the analysis of our present research.Another interesting aspect in VO 2 is that the T MIT can be modified by doping [8,9] and stress [10]. VO 2 thin films deposited on (001) and (110) TiO 2 substrates showed a modified T MIT of 27 and 96• C, respectively, where the c-axis length was stressed by a lattice mismatch between the film and the substrate [10]. The modification of the T MIT by doping and stress is restricted to within a fixed temperature, whereas the T MIT indu...

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supporting

confidence: 77%

Temperature dependence of the first-order metal-insulator transition in VO2 and programmable critical temperature sensor

Kim

Lee

Chae

et al. 2007

Applied Physics Letters

196

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“…The Raman spectrum of the Bragg filter sample A at 25 ℃ is shown in Fig. 2(a) [33,34]. This means even being encapsulated between two multilayer gratings, the defect layer is still an active polycrystalline VO2.…”

Section: Resultsmentioning

confidence: 99%

“…According to literature [33], the Raman shift at 612 cm -1 is able to characterize the hysteresis of the VO2 MIT phase transition. Heights of 612 cm -1 Raman shift of the Bragg filter sample are retrieved from Raman spectra under different temperatures and plotted in red in Fig.…”

Section: Resultsmentioning

confidence: 99%

Tunable Bragg filters with a phase transition material defect layer

Wang¹,

Gong²,

Dong³

et al. 2016

Opt. Express

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Abstract:We propose an all-solid-state tunable Bragg filter with a phase transition material as the defect layer. Bragg filters based on a vanadium dioxide defect layer sandwiched between silicon dioxide/titanium dioxide Bragg gratings are experimentally demonstrated. Temperature dependent reflection spectroscopy shows the dynamic tunability and hysteresis properties of the Bragg filter. Temperature dependent Raman spectroscopy reveals the connection between the tunability and the phase transition of the vanadium dioxide defect layer. This work paves a new avenue in tunable Bragg filter designs and promises more applications by combining phase transition materials and optical cavities. References and links1. E. Yablonovitch, "Inhibited spontaneous emission in solid-state physics and electronics," Phys. Rev. Lett. 2059-2062 (1987). 2. E. Yablonovitch, "Photonic band-gap structures," J. Opt. Soc. Am. B 10(2), 283-295 (1993) 1039-1263 (1998). 27. J. Wu, Q. Gu, B. S. Guiton, N. P. de Leon, L. Ouyang, and H. Park, "Strain-induced self organization of metal−insulator domains in single-crystalline VO2 nanobeams," Nano Lett. 6(10), 2313-2317 (2006). 28. A. Perucchi, L. Baldassarre, P. Postorino, and S. Lupi, "Optical properties across the insulator to metal transitions in vanadium oxide compounds," J. 58(20),

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“…2) and TEM/EELS analysis (not shown). The dominant Raman shifts and scattering arising from the TiO 2 support and additional overlap with V 2 O 5 bands prevented detection of discrete major VO 2 bands expected at 191, 258, and 335 cm −1 [36] and thus could not clarify the origin of the XRD patterns attributed to either VO 2 (B) or TiO 2 (B), respectively. Fig.…”

Section: Influence Of Preparation Variables On Structural Properties mentioning

confidence: 99%

Structure of Flame‐made Vanadia/Titania and Catalytic Behaviour in the Partial Oxidation of o‐Xylene

Schimmöller

Schulz

Ritter

et al. 2008

Chemie Ingenieur Technik

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Vanadia/titania particles with a specific surface area (SSA) up to 195 m 2 g −1 and a V 2 O 5 content up to 40% (w/w) or V coverage up to 59 V nm −2 were prepared by flame spray pyrolysis (FSP) under various conditions. The catalysts were characterized by nitrogen adsorption, X-ray diffraction, temperature-programmed reduction, and in situ Raman spectroscopy and tested for partial oxidation of o-xylene. Depending on vanadia content, monomeric, polymeric, and crystalline vanadia species were formed on TiO 2 support particles by FSP. Increasing the hightemperature particle residence time and concentration (production rate) during FSP reduced the SSA and increased the vanadia coverage of TiO 2 beyond a theoretical "monolayer" (>8-10 V nm −2 ) while retaining amorphous (monomeric and polymeric) VO x surface species. Controlling liquid precursor and dispersion gas feed rates, precursor concentration, and V 2 O 5 content allowed the tailoring of SSA and the population of the different VO x species in these vanadia/titania mixed oxides. For comparison, vanadia/titania catalysts containing 10% (w/w) V 2 O 5 with comparable SSA and V coverage were prepared by impregnation, resulting in typical amorphous (<10 V nm −2 ) and crystalline (>10 V nm −2 ) VO x species. Catalysts containing 7, 10, and 20% (w/w) V 2 O 5 were deposited directly from the flame on ceramic foams that were tested for the partial oxidation of o-xylene to phthalic anhydride. The global activity of flame-made and conventionally impregnated catalysts depended mainly on SSA and vanadia loading (number of V surface sites), whereas the amorphous or crystalline nature of the VO x species seemed to be less critical. In contrast, selectivity to phthalic anhydride was significantly affected by the nature of the VO x species; amorphous species exhibited higher selectivity for conversion <90% compared with catalysts containing crystalline V 2 O 5 .

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Raman microscopy analysis of phase transformation mechanisms in vanadium dioxide

Abstract: Raman microscopy is used to study the evolution of vibrational modes of vanadium dioxide single crystals and thin films in the vicinity of the phase transition. The results support the electron correlation model of phase transformation.

Cited by 166 publications

References 32 publications

Temperature dependence of the first-order metal-insulator transition in VO2 and programmable critical temperature sensor

Temperature dependence of the first-order metal-insulator transition in VO2 and programmable critical temperature sensor

Tunable Bragg filters with a phase transition material defect layer

Structure of Flame‐made Vanadia/Titania and Catalytic Behaviour in the Partial Oxidation of o‐Xylene

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