根據先前文獻研究指出Y3Co合金材料在溫度約160K附近其電阻率有不尋常的變化，可能存在電荷密度波的相變。為了解這材料相變特性，本研究測量Y3Co材料電阻率、比熱、熱導率、熱電功率、霍爾係數、磁化率以及核磁共振並針對相變溫度附近做進一步的討論。根據量測霍爾係數隨溫度變化的結果，研究發現電子載子在低溫時有減少的趨勢，從這個結果顯示出經過相變後電子費米面上有明顯的變化。另外，根據核磁共振的頻譜量測結果指出，在溫度低於相變溫度時，核磁共振的頻譜中央譜線沒有明顯變寬，顯示經過相變不是由磁性造成。

Previous studies have indicated that Y3Co undergoes a possible charge density wave (CDW) phase transition at T* ~ 160 K. In order to assess the phase transition nature in this compound, we have carried out the electrical resistivity, specific heat, thermal conductivity, Hall coefficient, Seebeck coefficient, magnetic susceptibility, and 59Co nuclear magnetic resonance (NMR) measurements, mainly focusing on the signatures around the phase transition temperature. The phase transition has been characterized by marked features near T* in all measured physical quantities. From a gradually increase in the magnitude of the Hall coefficient below T*, we conclude the reduction of negative charge carriers at low temperatures. Such a result indicates the significant modification in the electronic Fermi surfaces across the phase transition. In addition, the NMR spectra exhibit no visible line broadening below T*, excluding the magnetic origin for the observed phase transition.

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