Roles of the Narrow Electronic Band near the Fermi Level in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mn>1</mml:mn><mml:mi>T</mml:mi><mml:mtext>−</mml:mtext><mml:msub><mml:mrow><mml:mi>TaS</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub></mml:mrow></mml:math> -Related Layered Materials

Here we use low-temperature scanning tunneling microscopy and spectroscopy to reveal the roles of narrow electronic band in two 1$T$-TaS$_2$ related materials (bulk 4$H_{\rm b}$-TaS$_2$). b}$-TaS$_2$ is a superconducting compound with alternating 1$H$-TaS$_2$ layers, where layer has weak charge density wave (CDW) pattern reduces CDW coupling between adjacent layers. In b}$-TaS$_2$, observe located near Fermi level, its spatial distribution consistent tight-binding calculations for two-dimensional The hybridization layers shifts be slightly above which suppresses correlation induced splitting. contrast, bulk 1$T$-TaS$_2$, there an interlayer insulating gap. comparison distributions states gap results from formation bonding antibonding due overlap bands dimerized