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If the density of states vanishes over an extended energy range, then this is called a hard gap. If instead the density of states exactly vanishes only for a single energy value (while being suppressed, but not vanishing for nearby energy values), then this is called a soft gap. A prototypical
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If the density of states is suppressed near the Fermi energy but does not fully vanish, then this suppression is called
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Timusk, Tom; Statt, Bryan (1999). "The pseudogap in high-temperature superconductors: an experimental survey".
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the energy gap is a region of suppressed density of states around the
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437:(2nd ed.). McGraw-Hill.
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334:example of a soft gap is the
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302:{\displaystyle k_{\rm {B}}}
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82:See also:
43:vanishes.
25:energy gap
319:pseudogap
313:Pseudogap
219:Δ
170:Δ
35:where no
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433:(1996).
400:(1996).
365:(1976).
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58:Band gap
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