Gap Definition and 288 Threads

Gallium phosphide (GaP), a phosphide of gallium, is a compound semiconductor material with an indirect band gap of 2.24 eV at room temperature. Impure polycrystalline material has the appearance of pale orange or grayish pieces. Undoped single crystals are orange, but strongly doped wafers appear darker due to free-carrier absorption. It is odorless and insoluble in water.
GaP has a microhardness of 9450 N/mm2, a Debye temperature of 446 K (173 °C), and a thermal expansion coefficient of 5.3 ×10−6 K−1 at room temperature. Sulfur, silicon or tellurium are used as dopants to produce n-type semiconductors. Zinc is used as a dopant for the p-type semiconductor.
Gallium phosphide has applications in optical systems. Its static dielectric constant is 11.1 at room temperature. Its refractive index varies between ~3.2 and 5.0 across the visible range, which is higher than in most other semiconducting materials.

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  1. P

    What is the value of the band gap in a good conductor

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  2. N

    How to Find Subgroups of Index 2?

    Is anybody familiar with this program? Better yet, can someone explain to me how to find subgroups of index 2 (or index a power of 2)? Thanks.
  3. H

    Reducing Gap Around IC Chip Pins for 0.5mm Track

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  4. M

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  5. E

    Advice for Senior Physics/Math Major Planning a Gap Year

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  6. M

    Is it possible for electricity to jump a vacuum gap?

    Is it possible for electricity to jump a vacuum gap? If so, what is it called when that happens?
  7. H

    Understanding mass gap in Yang-Mills theory

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  8. C

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  9. T

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  10. S

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  11. magnetic flux

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  12. S

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  13. R

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  14. O

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  15. M

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  16. F

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  17. D

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  18. MathematicalPhysicist

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  19. C

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  20. M

    Band gap - violation of principle of least energy?

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  21. D

    Could a Billion-Year Technology Gap Exist?

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  22. H

    Energy Gap of Electron in Dirac Comb Potential

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  23. A

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  24. M

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  25. D

    Band Gap in Insulators: Values & Breakdown Voltage

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  26. G

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  27. J

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  28. F

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  29. Y

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  30. A

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  31. C

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  32. V

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  33. L

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  34. A

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  35. G

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  36. I

    Highery energy photon on lower band gap semiconductor

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  37. A

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  38. B

    Cyclotron accelerating protons to 20 MeV with potential gap 100 kV

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  39. madmike159

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  40. N

    What Does It Mean When the Fermi Level is in the Band Gap?

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  41. I

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  42. A

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  43. S

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  44. N

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  45. G

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  46. V

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  47. P

    What Is the Relationship Between Band Gap and Temperature in Germanium?

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  48. F

    News Gap in life expectancy in U.S. growing

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  49. E

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  50. G

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