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Hall Effect charge carrier trouble

  1. Aug 2, 2010 #1

    I recently did a Hall effect experiment with InSb. I did it in two parts. The first with the sample at room temperature and the second immersed in liquid nitrogen. I need some help understanding my results. I used the fomula v_h = (v_1 - v_2) / 2 to work out the Hall voltage (v_h). v_1 and v_2 are measured voltages for different orientations of the sample.

    For Part 1 (at room temperature)

    I measure voltages v_1 and v_2 for different values of current. I get + voltage for v_1 and - voltage for v_2. this leads to a positive value for v_h when I use the above formula for the Hall voltage. When I plot the Hall voltage against I, I get a positive slope. Can I conclude that the charge carriers are holes?

    Part 2 (in Liquid Nitrogen)

    Now I get positive values for v_1 and v_2. v_2 is greater than v_1 and this leads to negative values for v_h. when I plot v_h against I, i get a negative slope. Does this mean the charge carriers are now electrons?.

    Thank you.
  2. jcsd
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