近期的科爾偏角(Kerr rotation angle)實驗清楚地指出重費米子超導體UPt3的B相態有時間反轉對稱性破缺(time-reversal symmetry breaking)現象。採用當今廣為採信的配對對稱性E1g及E2u模型，我們嘗試單帶理論(one-band theory)計算超導光導電率(optical conductivity)藉以和實驗做比較。結果發現無論是E1g或E2u模型，單帶計算結果均不足以解釋實驗所觀察到的現象，主要原因是套入實驗用的1550 nm光波長，理論預測的科爾偏角效應比實驗觀察到的結果至少小兩個數量級以上。因此我們大膽猜測科爾偏角實驗在UPt3超導體看到的效應可能是不止單帶的貢獻。

Recent Kerr rotation angle experiments have revealed that time-reversal symmetry (TRS) is broken in B-phase of the unconventional heavy-fermion superconductor UPt3. Based on the widely used E1g and E2u pairing models, we perform a one-band calculation on the optical conductivity and compare the results with the experiments. It is shown that with one band, both E1g and E2u models fail to explain the data because at 1550 nm wavelength of the light used experimentally, the predicted effects are at least two orders of magnitude smaller than the observed ones. We argue that the observed Kerr rotation angle effect on superconducting UPt3 might be due to more than one band.

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