Measuring the thermoelectric effect of a simple metal

In summary, the thermoelectric effect can be formulated using the equation \mathbf{j} = \mathbf{\L}_{11}\mathbf{\xi} + \mathbf{\L}_{12}(-\mathbf{\nabla}T) and \mathbf{j} = \mathbf{\L}_{21}\mathbf{\xi} + \mathbf{\L}_{22}(-\mathbf{\nabla}T), where \mathbf{\L}_{ij} are tensors that characterize a given material. The easiest way to measure these coefficients is by using the Seebeck effect with two metals, with one of them being a known reference. Alternatively, a reference temperature can be used to obtain the See
  • #1
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By using the following formulation of the thermoelectric effect:

[tex]\mathbf{j} = \mathbf{\L}_{11}\mathbf{\xi} + \mathbf{\L}_{12}(-\mathbf{\nabla}T)[/tex]
[tex]\mathbf{j} = \mathbf{\L}_{21}\mathbf{\xi} + \mathbf{\L}_{22}(-\mathbf{\nabla}T)[/tex]

where [tex]\mathbf{\L}_{ij}[/tex] are tensors that charaterizes a given material.

What would be the easiest conceivable experiment to measure [tex]\mathbf{\L}_{ij}[/tex] of a certain material. One cannot exploit the Seebeck effect to get the ABSOLUTE VALUES of the coefficients of ONE METAL, since when you connect the leads of a voltmeter on the metal, it creates a temperature gradient inside of the meter itself (which would lead to false data). On the other hand, the use of the Peltier and Thomson effect leads to certain problems. I'm pretty sure that I must use one these effects to measure these coefficients, but I'm not sure how to do it .
:cry:
 
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  • #2
What if you use two metals, as in a thermocouple, with one of them a known reference? I think you can then figure out the unknown Seebeck coefficient from this.

If you really want to stick to one metal, I think you can use a reference temperature (passing one of the leads through ice or maintaining a point along the line at constant temperature.)

Either way, I think you can simply use the Seebeck effect.
 

1. What is the thermoelectric effect?

The thermoelectric effect is a phenomenon where an electric current is produced in a material when there is a temperature gradient across it. This effect is caused by the flow of heat energy from a hotter region to a cooler region, which generates a voltage difference.

2. How is the thermoelectric effect measured?

The thermoelectric effect can be measured by using a thermocouple, which is a device made of two different metals or semiconductors connected at two junctions. When there is a temperature difference between the two junctions, a voltage is generated which can be measured using a voltmeter.

3. What is a simple metal?

A simple metal is a type of metal that consists of only one type of atoms in its crystal structure. Examples of simple metals include copper, silver, and gold. These metals have high electrical conductivity, making them suitable for studying the thermoelectric effect.

4. How does the thermoelectric effect relate to temperature?

The thermoelectric effect is directly related to temperature. As the temperature difference between two junctions of a thermocouple increases, the voltage produced also increases. This relationship is known as the Seebeck effect and is the basis for measuring the thermoelectric effect.

5. What are the applications of the thermoelectric effect?

The thermoelectric effect has various applications, including temperature sensing, power generation, and refrigeration. It is commonly used in thermocouples for temperature measurements, in thermoelectric generators for converting heat energy into electricity, and in thermoelectric coolers for cooling electronic devices.

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