本篇實驗主題在砷化鎵/鋁砷化鎵異質接面的二維電子氣體系統中，觀察藉由外加微波在介觀系統下所引起的非線性現象，光致電壓效應(Photovoltaic Effect)。實驗量測是在溫度~2K，磁場0~6T的環境中進行，外加微波頻率為0.1GHz~38.5Ghz，外加微波方式為直接輻射以及輸入至樣品側金屬閘極，光致電壓效應的量測實驗中，沒有外加電流，所量測到的電壓值完全由微波所引起。
光致電壓效應的量測結果發現，再外加磁場下，光致電壓隨著磁場震動，且型式類似Shubnikov-de Hass震盪，且1/B的震盪週期與震盪相位都與SdH震盪相同。改變外加微波的功率，隨著微波功率的增減，光致電壓的震盪圖形並不會改變，微波功率只影響了光致電壓值的大小，量測結果顯示兩者為正相關。改變外加微波的頻率，霍爾平台出現前，光致電壓振盪的情形類似Shubnikov-de Hass震盪，兩種外加微波方式表現類似；霍爾平台出現後，兩種傳輸微波方式所量測到的光致電壓有了差異性：(1)微波直接輻射於樣品之上，在霍爾平台出現的範圍裡光致電壓皆趨近於零，不論改變微波的頻率或功率皆是如此。(2)微波外加至側金屬閘極，在霍爾平台出現的範圍裡光致電壓不一定趨近於零，當樣品尺寸較小，微波頻率較低時，霍爾平台範圍裡的光致電壓較容易出現額外的震盪。此外加微波方式的差異無法單純以微波影響費米面附近電子的圖像來解釋，可能有其他的貢獻。光致電壓效應在正負向磁場的對稱性：(1)微波直接輻射於樣品之上，反對稱項的貢獻大於對稱項，此情形與大部分的文獻相左，改變微波頻率對幅射下之對稱性沒有影響。(2) 微波外加至側金屬閘極，對稱項的貢獻大於反對稱項，增加微波頻率時，對稱項與反對稱項的貢獻漸趨相等，但對稱性變為較無規律性的震盪；增加樣品尺寸時，對稱項貢獻的比例也隨之增大。

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