【摘要】 利用紧束缚格林函数和计算机数值模拟方法,研究了4种单壁碳纳米管分子异质结的相干输运性质。结果表明:(5,5)/(8,0)和(5,5)/(10,0)的金属/半导体型异质结局域态密度出现了新的量子态;金属/金属型异质结(5,5)/(9,0)A和(5,5)/(9,0)B的量子电导小于完好的碳纳米管,但局域态密度增大;金属/金属型异质结的量子电导对碳纳米管的连接方式表现敏感,当给定的两种金属碳纳米管连接时,不同连接方式的异质结可能是导体、半导体、绝缘体。更多还原

【Abstract】 Coherent transport properties of four kinds of molecular heterojunctions of single-walled carbon nanotubes are studied by using the tight-binding green’s function and computer numerical simulation method.The calculation results show that,local state density of metal/semiconductor heterojunctions(5,5)/(8,0)composed of local density of states display appearance of new quantum states that allow electrons to pass through;Quantum conductance of metal/heterojunctions(5,5)/(8,0)composed of metal is less than the intact carbon nanotubes,and the local state density increased;Quantum conductance of metal/metal heterojunctions(5,5)/(9,0)A and(5,5)/(9,0)B are very sensitive to the linking manner of the carbon nanotubes,and when two given metallic carbon nanotubes are connected,heterojunctions formed in different liking manners may be conductors,semiconductors and insulators.更多还原