controlling phase change through ultrafast excitation of coherent phonons

... Controlling phase change through ultrafast excitation of coherent phonons Carl M. Liebig, Yaguo Wang, and Xianfan Xu* School of Mechanical Engineering and Birck ... demonstrating the possibility of controlling phase changes by coherent control of phonon oscillations. ©2010 Optical Society of America OCIS codes: (320.7130) Ultrafast processes in condense...

Ngày tải lên: 06/05/2014, 08:53

... of TeI atoms for excitation of A 1 1g and A 2 1g mode, respectively. The corresponding FFT spectra are shown in Figs. 3(c) and 3(d).It is seen that for the case of A 1 1g phonon excitation, coherent ... amplitude of reflectivity change. τ denotes the time constant (the decay time) of each process. , β, and ϕ stand for phonon angular frequency, chirping coefficient, and initial...

Ngày tải lên: 06/05/2014, 08:54

... of TeI atoms for excitation of A 1 1g and A 2 1g mode, respectively. The corresponding FFT spectra are shown in Figs. 3(c) and 3(d).It is seen that for the case of A 1 1g phonon excitation, coherent ... amplitude of reflectivity change. τ denotes the time constant (the decay time) of each process. , β, and ϕ stand for phonon angular frequency, chirping coefficient, and initial...

Ngày tải lên: 06/05/2014, 08:58

... reserved. 669 1.4 Phase change material layers The addition of a phase change material (PCM) into the external wall of a building has been shown to reduce the amount of energy required to ... Using Phase Change Materials. Energy Conversion and Management 2004, 45, 263-275. [14] Richardson M.J., Woods A.W., An Analysis of Phase Change Material as Thermal Mass. Pr...

Ngày tải lên: 05/09/2013, 15:28

... Abstract Storage of cooler night temperatures using Phase Change Material (PCM) energy storage technique, for cooling of ambient air during hot day times can be an alternate of current cooling ... the precision of the relationships for the 1998 ASHRAE database of field”. ASHRAE Transactions 2000, 206 (2), pp. 485-492. [12] K. Darkwa, P.W. O’Callaghan, “Simulation of pha...

Ngày tải lên: 05/09/2013, 17:03

Ngày tải lên: 16/03/2014, 03:20

... observation of coherent phonons generated in semi- metals ͑Bi, Sb͒ and semiconductors ͑Te, Ti 2 O 3 ͒. 1–3 The gen- eration of coherent phonon is attributed to a mechanism called displacive excitation of ... position. 4 Such coherent phonon vibration can be detected by a time- resolved reflectivity measurement. The large reflectivity change ⌬R/R ͑10 −3 –10 −2 ͒ of coherent...

Ngày tải lên: 06/05/2014, 08:55

... trans! missivity of the excimer laser beam through the laser! evaporated plume[ Results of the numerical simulation compare well with the experimentally determined threshold value of the onset of explosive phase ... superheated liquid to a mixture of vapor and liquid droplets[ The explosive phase change phenomenon was _rst investigated in detail in the earlier work of puls...

Ngày tải lên: 06/05/2014, 08:55

... and phase change of an argon crystal illuminated with a picosecond pulsed laser are investigated using molecular dynamics simulations. The result reveals no clear interface when phase change ... 0.5414 nm c r , Cut off distance 0.8515 nm Size of the sample – x 48.726 nm Size of the sample –y 48.726 nm Size of the sample –z 8.121 nm Time step 25 fs Number of atoms...

Ngày tải lên: 06/05/2014, 08:55

... and phase change of an argon crystal illuminated with a picosecond pulsed laser are investigated using molecular dynamics simulations. The result reveals no clear interface when phase change ... 0.5414 nm c r , Cut off distance 0.8515 nm Size of the sample – x 48.726 nm Size of the sample –y 48.726 nm Size of the sample –z 8.121 nm Time step 25 fs Number of atoms...

Ngày tải lên: 06/05/2014, 08:57