What is Gap: Definition and 288 Discussions

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. cnh1995

    Spark Gap Transmitter: EM Wave Generation & Transmission

    I recently read about the early spark gap transmitter..But I don't understand how the EM waves are generated and transmitted..Induction coil creates sparks in the gap but what produces the waves and how are they transmitted?? Need I study electromagnetic waves in detail??
  2. U

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  3. F

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  4. NaOH

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  5. A

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  6. G

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  8. R

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  9. P

    Math, Physics, and Engineering: Bridging the Gap

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  10. C

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  11. G

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  12. A

    Why doesn't Graphene have a band gap?

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  13. Pythagorean

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  14. K

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  15. H

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  16. N

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  17. H

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  18. G

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  20. F

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  21. O

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  22. F

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  23. marellasunny

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  24. A

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  25. C

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  26. B

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  29. G

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  31. E

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  32. A

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  33. abhishek99087

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  34. A

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  35. A

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  36. mcodesmart

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  37. B

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  38. M

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  39. I

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  40. Seydlitz

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  41. J

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  42. D

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  43. J

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  44. supak111

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  45. A

    What Factors Influence the Band Gap in Band Structures?

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  46. G

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  47. marcus

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  48. N

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  49. S

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  50. D

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