Souers P C, Jura G
Science. 1964 Jan 31;143(3605):467-9. doi: 10.1126/science.143.3605.467.
Measurements of the electrical resistance have been made on bismuth 1 between 15 and 35 kilobars at temperatures between 77.4 degrees and 120 degrees K. Above about 150 degrees K, the temperature coefficient of resistance is positive, as in a metal; below 150 degrees K, the coefficient becomes negative, as is characteristic of semiconductors. On the basis that bismuth is a semiconductor, the energy gap, calculated by the exponential resistance formula, is 0.006 ev at 15 kb with a steady rise to 0.018 ev at 35 kb. At higher pressures, bismuth I is transformed into a metallic modification with the normal temperature dependence of the resistance. The energy gap in bismuth I is not visible at room temperature because thermal excitation populates the conduction band and metallic behavior is the result. From available evidence the observed behavior is due to an energy gap rather than to a decrease in carrier mobility.
在77.4开尔文至120开尔文的温度范围内，对处于15至35千巴压力下的铋1进行了电阻测量。高于约150开尔文时，电阻温度系数为正，如同金属；低于150开尔文时，该系数变为负，这是半导体的特征。基于铋是半导体这一前提，根据指数电阻公式计算得出，在15千巴时能隙为0.006电子伏特，在35千巴时稳定上升至0.018电子伏特。在更高压力下，铋1转变为具有正常电阻温度依赖性的金属变体。铋1中的能隙在室温下不可见，因为热激发使导带充满，从而导致金属行为。根据现有证据，观察到的行为是由于能隙而非载流子迁移率的降低。
