What are J-FET transistors, and how do they work?

I'd like a fairly accurate and not incredibally answer is complex. Note: I am primarily interested in physics. Note: I'm mostly interested in physics (yeah, I probably should have asked this question in another section, but apparentally yahoo will not let me change it.

If my memory serves ... J-FET has three terminals .. gate, source and drain. It works, almost like plumbing parts terminals are named after. The current is allowed to flow from source to the drain voltage at the gate is raised.

2x 3N328A Low Noise GaAs Dual Gate FET transistor 1 8 GHz
2x 3N328A Low Noise GaAs Dual Gate FET transistor 1 8 GHz
$7.88
Time Remaining: 4h 40m
Buy It Now for only: $7.88

IRFPC50 IRFPC50PBF 600V 11A 180W FET NEW
IRFPC50 IRFPC50PBF 600V 11A 180W FET NEW
$8.99
Time Remaining: 6h 35m
Buy It Now for only: $8.99

30 AS4428 DUAL FET DRIVER 45 18V 50ns 10 15A PEAK SOIC 8 SMD SMT MOSFET
30 AS4428 DUAL FET DRIVER 45 18V 50ns 10 15A PEAK SOIC 8 SMD SMT MOSFET
$3.99
Time Remaining: 7h 38m
Buy It Now for only: $3.99

2SJ307 P FET 250 V 6 A 2 W BY SANYO LOT OF 10
2SJ307 P FET 250 V 6 A 2 W BY SANYO LOT OF 10
$29.00
Time Remaining: 10h 16m
Buy It Now for only: $29.00

5 PCS 2SK4213 TO 252 K4213 SWITCHING N CHANNEL POWER MOS FET
5 PCS 2SK4213 TO 252 K4213 SWITCHING N CHANNEL POWER MOS FET
$6.36
Time Remaining: 11h 27m
Buy It Now for only: $6.36

5 PCS 2SK2414 TO 252 K2414 SWITCHING N CHANNEL POWER MOS FET INDUSTRIAL USE
5 PCS 2SK2414 TO 252 K2414 SWITCHING N CHANNEL POWER MOS FET INDUSTRIAL USE
$5.69
Time Remaining: 11h 27m
Buy It Now for only: $5.69

SD211DE SILICONIX 2SD211DE FET Transistor GOLD LEADS METAL CAN NOS
SD211DE SILICONIX 2SD211DE FET Transistor GOLD LEADS METAL CAN NOS
$11.95
Time Remaining: 13h 35m
Buy It Now for only: $11.95

10 PCS 2SK1413 N channel MOS FET K1413 Transistor The best price on Ebay
10 PCS 2SK1413 N channel MOS FET K1413 Transistor The best price on Ebay
$28.00
Time Remaining: 14h 14m
Buy It Now for only: $28.00

Qty 11 Motorola U308 N CH Transistor FET VHF UHF NOS Gold Plated
Qty 11 Motorola U308 N CH Transistor FET VHF UHF NOS Gold Plated
$19.99
Time Remaining: 16h 36m
Buy It Now for only: $19.99

SPI SD214DE N CHANNEL FET TRANSISTOR  SD214
SPI SD214DE N CHANNEL FET TRANSISTOR SD214
$3.50
Time Remaining: 18h 52m
Buy It Now for only: $3.50

10pcs Transistor IRF4905 IRF4905PBF MOSFET FET P Channel 55V 75A 200W DIY
10pcs Transistor IRF4905 IRF4905PBF MOSFET FET P Channel 55V 75A 200W DIY
$5.18
Time Remaining: 21h 30m
Buy It Now for only: $5.18

50 Harris IRFD9113 P CHANNEL FET 80V 06A 16 DIP 4 MOSFET POWER TRANSISTOR
50 Harris IRFD9113 P CHANNEL FET 80V 06A 16 DIP 4 MOSFET POWER TRANSISTOR
$3.99
Time Remaining: 22h 50m
Buy It Now for only: $3.99

10pcs SMD IRLML6401 TRPBF FET Field Effect Transistor MOSFET P channel 12V 43A
10pcs SMD IRLML6401 TRPBF FET Field Effect Transistor MOSFET P channel 12V 43A
$2.22
Time Remaining: 1d 52m
Buy It Now for only: $2.22

MMBFJ310 N Channel FET 25V 350mW Transistor SOT 23 SMD Qty 25
MMBFJ310 N Channel FET 25V 350mW Transistor SOT 23 SMD Qty 25
$14.99
Time Remaining: 1d 1h 18m
Buy It Now for only: $14.99

MMBFJ201 40V N Channel FET Transistor SOT 23 SMD Qty 25
MMBFJ201 40V N Channel FET Transistor SOT 23 SMD Qty 25
$14.99
Time Remaining: 1d 1h 19m
Buy It Now for only: $14.99

10pcs SMD IRLML6401 TRPBF FET Field Effect Transistor MOSFET P channel 12V 43
10pcs SMD IRLML6401 TRPBF FET Field Effect Transistor MOSFET P channel 12V 43
$2.21
Time Remaining: 1d 2h 38m
Buy It Now for only: $2.21

10 pcs IRFBE30 HEXFET Power MOSFET FET HEX MOS
10 pcs IRFBE30 HEXFET Power MOSFET FET HEX MOS
$14.99
Time Remaining: 1d 7h 1m
Buy It Now for only: $14.99

FHC40LG 2 12 GHz Super Low Noise HEMT FET
FHC40LG 2 12 GHz Super Low Noise HEMT FET
$9.99
Time Remaining: 1d 9h 5m
Buy It Now for only: $9.99

Lot Of 10 2SK901 N channel Silicon Power MOS FET 250V 20A
Lot Of 10 2SK901 N channel Silicon Power MOS FET 250V 20A
$14.95
Time Remaining: 1d 10h 17m
Buy It Now for only: $14.95

IR INTERNATIONAL RECTIFIER JAN JANTX2N6768 MIL 2N6768 FET 400V 15A N MOSFET NOS
IR INTERNATIONAL RECTIFIER JAN JANTX2N6768 MIL 2N6768 FET 400V 15A N MOSFET NOS
$7.99
Time Remaining: 1d 12h 35m
Buy It Now for only: $7.99

IR INTERNATIONAL RECTIFIER JAN JANTX2N6849 MIL 2N6849 FET 100V 6A P HEXFET TO 39
IR INTERNATIONAL RECTIFIER JAN JANTX2N6849 MIL 2N6849 FET 100V 6A P HEXFET TO 39
$9.99
Time Remaining: 1d 12h 43m
Buy It Now for only: $9.99

SIEMENS BSS124E7984 MOS FET TRANSISTOR 400V 12A TO 92
SIEMENS BSS124E7984 MOS FET TRANSISTOR 400V 12A TO 92
$9.90
Time Remaining: 1d 14h 34m
Buy It Now for only: $9.90

2SD215DE SD215DE SILICONIX FET Transistor TIN METAL CAN
2SD215DE SD215DE SILICONIX FET Transistor TIN METAL CAN
$11.95
Time Remaining: 1d 14h 56m
Buy It Now for only: $11.95

80N04 NEC SWITCHING N CHANNEL POWER MOS FET 40V 80A NP80N04CHE S12 AZ QTY1
80N04 NEC SWITCHING N CHANNEL POWER MOS FET 40V 80A NP80N04CHE S12 AZ QTY1
$7.00
Time Remaining: 1d 15h 12m
Buy It Now for only: $7.00

TNM1800 7 TOSHIBA MICROWAVE POWER GaAs FET Gold
TNM1800 7 TOSHIBA MICROWAVE POWER GaAs FET Gold
$199.95
Time Remaining: 1d 18h 36m
Buy It Now for only: $199.95

TIM7785 14L TOSHIBA MICROWAVE POWER GaAs FET Gold
TIM7785 14L TOSHIBA MICROWAVE POWER GaAs FET Gold
$249.95
Time Remaining: 1d 18h 42m
Buy It Now for only: $249.95

TIM5053 8 TOSHIBA MICROWAVE POWER GaAs FET Gold
TIM5053 8 TOSHIBA MICROWAVE POWER GaAs FET Gold
$199.95
Time Remaining: 1d 18h 47m
Buy It Now for only: $199.95

vn0104n3 vertical DMOS FET CANAL N
vn0104n3 vertical DMOS FET CANAL N
$3.98
Time Remaining: 1d 21h 41m
Buy It Now for only: $3.98

10x ZETEX ZVP2110A MOSFET DMOS 100V P CH E LINE FET TO 92 NEW
10x ZETEX ZVP2110A MOSFET DMOS 100V P CH E LINE FET TO 92 NEW
$8.88
Time Remaining: 1d 21h 47m
Buy It Now for only: $8.88

10x ZETEX ZVN2110A MOSFET DMOS 100V N CH E LINE FET TO 92 NEW
10x ZETEX ZVN2110A MOSFET DMOS 100V N CH E LINE FET TO 92 NEW
$7.48
Time Remaining: 1d 22h 12m
Buy It Now for only: $7.48

10x ZETEX ZVP3310A MOSFET DMOS 100V P CH E LINE FET TO 92 NEW
10x ZETEX ZVP3310A MOSFET DMOS 100V P CH E LINE FET TO 92 NEW
$8.98
Time Remaining: 1d 22h 18m
Buy It Now for only: $8.98

10 PCS 2SK2018 01S TO 252 2SK2018 K2018 01S K2018 FUJI N channel MOS FET NEW
10 PCS 2SK2018 01S TO 252 2SK2018 K2018 01S K2018 FUJI N channel MOS FET NEW
$8.26
Time Remaining: 2d 4h 25m
Buy It Now for only: $8.26

2 PCS FQPF4N90C FQPF 4N90C MOSFET 900V N Ch Q FET advance TO 220F FSC New
2 PCS FQPF4N90C FQPF 4N90C MOSFET 900V N Ch Q FET advance TO 220F FSC New
$3.59
Time Remaining: 2d 7h 8m
Buy It Now for only: $3.59

2 PCS FQP4N90C FQP 4N90C MOSFET 900V N Ch Q FET advance TO 220 FSC New
2 PCS FQP4N90C FQP 4N90C MOSFET 900V N Ch Q FET advance TO 220 FSC New
$3.99
Time Remaining: 2d 7h 8m
Buy It Now for only: $3.99

10 PCS FQPF4N90C FQPF 4N90C MOSFET 900V N Ch Q FET advance TO 220F FSC New
10 PCS FQPF4N90C FQPF 4N90C MOSFET 900V N Ch Q FET advance TO 220F FSC New
$14.99
Time Remaining: 2d 7h 8m
Buy It Now for only: $14.99

3 NEW JVC 2SK2042 FET MOSFET TRANSISTORS AUDIO AMPLIFIERS SWITCHING
3 NEW JVC 2SK2042 FET MOSFET TRANSISTORS AUDIO AMPLIFIERS SWITCHING
$9.95
Time Remaining: 2d 8h 55m

2 x K10A50D TK10A50D Genuine Toshiba Fet Transistor + Heat Sink Compound
2 x K10A50D TK10A50D Genuine Toshiba Fet Transistor + Heat Sink Compound
$2.95
Time Remaining: 2d 10h 47m
Buy It Now for only: $2.95

2 x K10A60D TK10A60D Genuine Toshiba Fet Transistor + Heat Sink Compound
2 x K10A60D TK10A60D Genuine Toshiba Fet Transistor + Heat Sink Compound
$6.95
Time Remaining: 2d 11h 2m
Buy It Now for only: $6.95

10 2N5951 FET N Ch RF AMP TRANSISTORS  NEW
10 2N5951 FET N Ch RF AMP TRANSISTORS NEW
$4.00
Time Remaining: 2d 12h 30m
Buy It Now for only: $4.00

2SK513 N FET 800 V 3 A 60 W
2SK513 N FET 800 V 3 A 60 W
$2.95
Time Remaining: 2d 13h 4m
Buy It Now for only: $2.95

2SK525 N FET 150V 10A 40W
2SK525 N FET 150V 10A 40W
$4.95
Time Remaining: 2d 13h 10m
Buy It Now for only: $4.95

50 FDC5614P P CHANNEL FET 60V 3A 135m LOGIC LEVEL SOT 6 SMD SMT TRANSISTOR
50 FDC5614P P CHANNEL FET 60V 3A 135m LOGIC LEVEL SOT 6 SMD SMT TRANSISTOR
$1.99
Time Remaining: 2d 14h 22m
Buy It Now for only: $1.99

Fairchild NDS352AP P Ch FET 30V 900mA SOT 23 10pcs
Fairchild NDS352AP P Ch FET 30V 900mA SOT 23 10pcs
$5.99
Time Remaining: 2d 15h 22m
Buy It Now for only: $5.99

2SJ449 P FET 250V 6A 35W BY NEC
2SJ449 P FET 250V 6A 35W BY NEC
$1.75
Time Remaining: 2d 15h 37m
Buy It Now for only: $1.75

2SK1058+2SJ162 N FET 160V 7A 100W BY HIT
2SK1058+2SJ162 N FET 160V 7A 100W BY HIT
$9.95
Time Remaining: 2d 15h 54m
Buy It Now for only: $9.95

2SK1058 N FET 160V 7A 100W BY HIT
2SK1058 N FET 160V 7A 100W BY HIT
$6.95
Time Remaining: 2d 15h 56m
Buy It Now for only: $6.95

BUK7516 55A N Channel Power FET Transistor
BUK7516 55A N Channel Power FET Transistor
$1.50
Time Remaining: 2d 16h 17m
Buy It Now for only: $1.50

Lot Of 10 2SK902 N channel Silicon Power MOS FET 250V 30A
Lot Of 10 2SK902 N channel Silicon Power MOS FET 250V 30A
$14.95
Time Remaining: 2d 18h 23m
Buy It Now for only: $14.95

PN4392 N CHANNEL J FET
PN4392 N CHANNEL J FET
$8.75
Time Remaining: 2d 21h 22m
Buy It Now for only: $8.75

PD55003L E Power Transistor Microwave N Channel FET LDMOST PD55003L 5Pcs
PD55003L E Power Transistor Microwave N Channel FET LDMOST PD55003L 5Pcs
$15.00
Time Remaining: 2d 22h 49m
Buy It Now for only: $15.00

1pc FQA9N90C 9N90C 9N90 FET TO 3P
1pc FQA9N90C 9N90C 9N90 FET TO 3P
$3.99
Time Remaining: 3d 23m
Buy It Now for only: $3.99

5pcs FQA9N90C 9N90C 9N90 FET TO 3P
5pcs FQA9N90C 9N90C 9N90 FET TO 3P
$9.29
Time Remaining: 3d 23m
Buy It Now for only: $9.29

10pcs FQA9N90C 9N90C 9N90 FET TO 3P
10pcs FQA9N90C 9N90C 9N90 FET TO 3P
$16.19
Time Remaining: 3d 23m
Buy It Now for only: $16.19

10pcs 2SK30A Y 2SK30A 2SK30 MOS FET Transistor Transistors
10pcs 2SK30A Y 2SK30A 2SK30 MOS FET Transistor Transistors
$3.53
Time Remaining: 3d 1h 43m
Buy It Now for only: $3.53

J211 N Channel RF Amplifier FET Transistor TO 92 Qty 50
J211 N Channel RF Amplifier FET Transistor TO 92 Qty 50
$19.99
Time Remaining: 3d 1h 49m
Buy It Now for only: $19.99

J111 N Channel 35V 50mA FET Transistor Switch TO 92 Qty 20
J111 N Channel 35V 50mA FET Transistor Switch TO 92 Qty 20
$12.99
Time Remaining: 3d 1h 49m
Buy It Now for only: $12.99

2N7000 N Channel Enhancement Mode Transistor FET TO 92 Qty 200
2N7000 N Channel Enhancement Mode Transistor FET TO 92 Qty 200
$23.99
Time Remaining: 3d 1h 55m
Buy It Now for only: $23.99

BS270 N Channel Enhancement Mode FET 60V 400mA Transistor TO 92 Qty 50
BS270 N Channel Enhancement Mode FET 60V 400mA Transistor TO 92 Qty 50
$15.99
Time Remaining: 3d 1h 55m
Buy It Now for only: $15.99

MTP3055VL 60V 12A N Channel Field Effect Transistor FET TO 220 MTP3055 Qty 10
MTP3055VL 60V 12A N Channel Field Effect Transistor FET TO 220 MTP3055 Qty 10
$14.99
Time Remaining: 3d 1h 55m
Buy It Now for only: $14.99

2N7002 N Channel FET Enhancement Mode Transistor SMD SOT 23 Qty 500
2N7002 N Channel FET Enhancement Mode Transistor SMD SOT 23 Qty 500
$20.99
Time Remaining: 3d 1h 55m
Buy It Now for only: $20.99

BS170 N Channel Enhancement Mode FET Transistor TO 92 Qty 50
BS170 N Channel Enhancement Mode FET Transistor TO 92 Qty 50
$9.99
Time Remaining: 3d 2h 1m
Buy It Now for only: $9.99

BS170 N Channel Enhancement Mode FET Transistor TO 92 Qty 200
BS170 N Channel Enhancement Mode FET Transistor TO 92 Qty 200
$25.99
Time Remaining: 3d 2h 1m
Buy It Now for only: $25.99

MMBFJ177 P Channel FET 30V 225mW Transistor Switch SMD SOT 23 Qty 25
MMBFJ177 P Channel FET 30V 225mW Transistor Switch SMD SOT 23 Qty 25
$14.99
Time Remaining: 3d 2h 1m
Buy It Now for only: $14.99

IRFB11N50APBF HEXFET Power MOSFET N Channel IRFB11N50 HEX FET 5Pcs
IRFB11N50APBF HEXFET Power MOSFET N Channel IRFB11N50 HEX FET 5Pcs
$6.50
Time Remaining: 3d 2h 38m
Buy It Now for only: $6.50

Qty 2 Fujitsu FSX027WF GaAs FET RF Microwave Transistor 12 GHz NOS
Qty 2 Fujitsu FSX027WF GaAs FET RF Microwave Transistor 12 GHz NOS
$22.00
Time Remaining: 3d 2h 40m
Buy It Now for only: $22.00

IRFB11N50APBF HEXFET Power MOSFET N Channel IRFB11N50 HEX FET 100Pcs
IRFB11N50APBF HEXFET Power MOSFET N Channel IRFB11N50 HEX FET 100Pcs
$110.00
Time Remaining: 3d 2h 41m
Buy It Now for only: $110.00

Qty 9 Fujitsu FLL500IQ 2 GaAs FET RF Microwave Transistors High Power GaAsFET
Qty 9 Fujitsu FLL500IQ 2 GaAs FET RF Microwave Transistors High Power GaAsFET
$80.00
Time Remaining: 3d 2h 42m
Buy It Now for only: $80.00

Pack of 20 Fujitsu FSX52WF GaAs FET RF Microwave Transistor 8 GHz NOS IN BOX
Pack of 20 Fujitsu FSX52WF GaAs FET RF Microwave Transistor 8 GHz NOS IN BOX
$160.00
Time Remaining: 3d 2h 53m
Buy It Now for only: $160.00

10pcs 2SK30A Y 2SK30A 2SK30 MOS FET Transistor Transistors
10pcs 2SK30A Y 2SK30A 2SK30 MOS FET Transistor Transistors
$3.52
Time Remaining: 3d 3h 38m
Buy It Now for only: $3.52

2SK117 GR TOSHIBA Low Noise Audio Amplifier J FET x20
2SK117 GR TOSHIBA Low Noise Audio Amplifier J FET x20
$18.00
Time Remaining: 3d 8h 20m
Buy It Now for only: $18.00

TIS74 N Channel FET GP Amplifier NSC  National Semiconductor  12pcs per lot
TIS74 N Channel FET GP Amplifier NSC National Semiconductor 12pcs per lot
$5.93
Time Remaining: 3d 9h
Buy It Now for only: $5.93

Transistor  Dual FET 8 pin DIP  NPD5566
Transistor Dual FET 8 pin DIP NPD5566
$14.99
Time Remaining: 3d 9h
Buy It Now for only: $14.99

Philips BUK456 800B N Channel FET Lot of 5
Philips BUK456 800B N Channel FET Lot of 5
$8.95
Time Remaining: 3d 10h 7m
Buy It Now for only: $8.95

Qty 1 NEC NES1823P 50 50 Watt 22 GHz GaAs MES FET Microwave Transistor New
Qty 1 NEC NES1823P 50 50 Watt 22 GHz GaAs MES FET Microwave Transistor New
$20.00
Time Remaining: 3d 10h 10m
Buy It Now for only: $20.00

Qty 1 Toshiba TPM1818 14 GaAs FET RF Microwave Transistor 18 GHz NEW
Qty 1 Toshiba TPM1818 14 GaAs FET RF Microwave Transistor 18 GHz NEW
$25.00
Time Remaining: 3d 10h 10m
Buy It Now for only: $25.00

Qty 1 NEC NES1821B 30 30 Watt 18 21 GHz GaAs MES FET Microwave Transistor
Qty 1 NEC NES1821B 30 30 Watt 18 21 GHz GaAs MES FET Microwave Transistor
$25.00
Time Remaining: 3d 10h 10m
Buy It Now for only: $25.00