本論文的主要目的在研究高溫超導體YBCO樣品在不同電流、不同磁場大小之下，羅倫茲力與溫度的關係。我們利用電子天平與一組C型磁鐵置於樣品兩側當做外加磁場，並且在不同溫度下，外加電流直接量測作用在C型磁鐵力與溫度的關係，並紀錄電壓值。經由探討所得到的數據，我們發現YBCO在正常態，所量得的力與羅倫茲力公式符合( F=I L×B)；在混合態時量得力卻有高於羅倫茲力的現象；在超導態下，因釘札力過大而量測的力為零。我們引用磁通子移動時所產生drag force來說明磁通子在混合態為何有高於羅倫茲力的現象。 This article is to study the Lorentz force for various current and magnetic field as function of temperature on high-temperature Superconductor YBCO. We measure force and voltage by using a electronic balance and a voltmeter. We use a C-type magnet to apply magnetic field to our sample. From our experimental data, it is found that when YBCO is in normal state, the force satisfies Lorentz force (F=I L×B). In mixed state, the force is larger than Lorentz force. We use the flux drag force that acts on vortex to explain this situation. In superconducting state, the force is zero because the pinning force is too large.
