The wavefunction of a single spin system in a prepared initial state evolves to equilibrium with a heat bath. The average spin q(t) = p↑(t)− p↓(t) exhibits a characteristic time for this evolution. With the proper choice of spin flip rates, a dynamical Ising model (Glauber) can be constructed with the same characteristic time for transition of the average spin to equilibrium. The Glauber dynami...

We work out the method for evaluating the QCD coupling constant at finite temperature (T ) by making use of the finite T renormalization group equation up to the one-loop order on the basis of the background field method with the imaginary time formalism. The background field method, which maintains the explicit gauge invariance, provides notorious simplifications since one has to calculate onl...

approved: enri J.F. Jansen Molecular dynamics is a technique in which the trajectories of a group of particles are calculated as a function of time by integrating the equations of motion. In this thesis we study the use of molecular dynamics for atoms in a crystal. A model is introduced which describes interactions of a physical system with an external heat reservoir in molecular dynamics simul...

The evaluation of response time of a constant temperature thermoresistive sensor based feedback circuit, excited by a pulsewidth modulated (PWM) waveform is done by a way of simulation studies in PSPICE environment and compared with that of a circuit excited by an analog voltage (continuous time domain). For a thermoresistive sensor with an intrinsic time constant much larger than the period of...

Tetracene thin films are investigated by time-resolved photoluminescence on picosecond to nanosecond time-scales. The picosecond luminescence decay dynamics is confirmed to be independent of temperature, but the nanosecond timescale luminescence dynamics is highly temperature dependent. This is interpretted in terms of motion along an intermolecular coordinate which couples the S1 state to the ...