TSDC热激励去极化电流测量

热激励去极化电流（thermally stimulated depolarization currents, 简写为TSDC或TSC）是电介质材料在受热过程中建立极化态或解除极化态时所产生的短路电流。基本方法是将试样夹在两电极之间，加热到一定温度使样品中的载流子激发，然后施加一个直流的极化电压，经过一段时间使样品充分极化，以便载流子向电极漂移或偶极子充分取向，随后立即降温到低温，使各类极化“冻结”，然后以等速率升温，同时记录试样经检流计短路的去极化电流随温度的变化关系，即得到TSDC谱。通过TSDC谱研究介质材料中偶极子和可动离子的性质、激活能（或陷阱深度）、以及弛豫时间（寿命）等。

 

General Features

All TSDC (Thermal Stimulated Depolarization Current) measurements are supported by computer control and Windows-based software WinTSDC. It operates the polarization voltage source, the polarization/depolarization mode switches, the high sensitive and fast electrometer for sensing the depolarization current and several temperature control systems. Nearly any kind of TSDC experiment can be programmed by a flexible experiment set-up procedure. The experiment is defined by a series of time intervals. During each time interval, the polarization voltage and temperature is either defined as fixed value or with a continuously change in time (ramp). The system may be switched in each time interval between the polarization and depolarization current measurement mode. In addition to this general experiment set-up mode, predefined set-ups like e. g. batch modes for series of TSDC sweeps with different heating rates are supported.

The basic TSDC parameters, like depolarization current as a function of temperature are evaluated and displayed graphically in single or multicurve representation and exported numerically. In another representation, the experiment state defined by polarization voltage, temperature and depolarization current is shown as a function of time.

Optional Thermal Windowing

In addition to the standard TSDC functions, the thermal windowing technique can be performed by the TSDC system, which is requiring additional experiment conditions and optional software.

It supports data manipulation functions like shifting, deleting of data points, and confining and smoothing of data curves. The main function of this software is the evaluation of relaxation maps from a thermal windowing experiment. The sample polarization is calculated by numerical integration from the measured depolarization current. Several procedures for integration and base line corrections are supported. After the conversion of the polarization and depolarization current into the relaxation time, the common relaxation maps are created. They show the single Debye relaxation modes in several representations like e. g. Arrhenius or a free energy diagram. Several curve fitting model functions like Arrhenius, Vogel Fulcher and Williams Landel Ferry (WLF) for the relaxation time data are supported.

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