½ ¨ 7 Hë H Sae Mulli (The Korean Physical Society), Volume 57, Number 5, 2008¸ 11 Z 4, pp. 338∼341
mø m Ç my ¢= k ° Ë Ñ Ö « ×M õ u § T Ó Þ X ¢ : 0z ºÆ U Ø ¹ Å° Ë Ñ OR À X ØP 4 T ² 8 ý { ¢8 ý÷ m Ç] M ö
_
@* å ? ∗ · »` 9 Ú
ô
Dz D G õ < Æl Õ ü t ½ ¨" é ¶, t 0 p x r Û ¼% 7 ½ ¨ : r  Ò, " fÖ ¦ 136-791 (2008¸ 9 Z 4 26{ 9 ~ à Î6 £ §)
ì
ø Í ¸^ F g7 £ x; ¤ l (SOA)_ s 1 p q í o\ ¦ s 6 x ô Ç D h Ðî r F g OR 7 H o è ô Ç > h_ SOA\ ¦ s 6 x
# ] jî ß ÷ & ¦ VPI r Ó ý t Y Us ' \ ¦ s 6 x # $ í / B N& h Ü ¼ Ð ½ ¨ & ³÷ &% 3 . F g OR 7 H o > s à Ô_ 1 l x : £ ¤
$ í
É r ¸ ñü < * 3 á Ô ñ Ð ½ ©g Ë :& h ñ J õ Ô ¦ ½ ©g Ë :& h ñ J ` ¦ s 6 x # 10 Gbps\ " f
%
6 £ § Ü ¼ Ð ¸_ z ´+ « >s s À Ò# Q& .
PACS numbers: 42.25.Bs
Keywords: F g OR 7 H o è , ì ø Í ¸^ F g7 £ x; ¤ l , Cross-gain modulation(XGM)
I. " e  ] Ø
p
A & ñ Ð : x } © _ 3 l q& h É r 6 £ §$ í ñ, & ñ t % ò © , 1 l x% ò
© 1 p x _ Y O w p n # Q " fq Û ¼\ ¦ ] j/ B N H כ s l M :ë H \ l
ç ß } © _ & ñ Ð% o 6 x | ¾ Ós à ºÑ þ Gbps РÒ' à º Tbps Ð 7
£
x | ¨ c } © s . þ j H \ @ /6 x | ¾ Ó_ X <s ' \ ¦ ¦5 Å q Ü ¼ Ð
5 Å x, % o , § ¨ 8 l 0 AK F g ñ% o l Õ ü t s Ù þ d l
Õ ü t Ð @ /¿ º÷ & ¦ e . : £ ¤ y , 4 ¤ ¸ ú ô Ç l - F g < Æ ¨ 8 ` ¦ x
½ + É Ã º e H F g 7 H o 1 l x É r F g ñ % o r Û ¼% 7 _ Ù þ
d l Õ ü t s . Õ ª QÙ ¼ Ð [ j@ / F g( É Óh A x 9 F g ñ
%
o ì r \ " f × æ כ ¹ô Ç F g 7 H o è _ l Õ ü t > hµ 1 Ïs þ j
H t Ö ¸ µ 1 Ïy s À Ò# Qt ¦ e .
t
F K t í ¦5 Å q F g& ñ Ð% o \ ¦ 0 Aô Ç F g 7 H o è H Å
Ò Ð ì ø Í ¸^ F g7 £ x; ¤ l (Semiconductor Optical Ampli- fier: SOA) _ q + þ A : £ ¤$ í ` ¦ s 6 x ¦ e . : £ ¤ y , F g OR 7 H o è H SOA _ q + þ A s 1 p q õ Ï ã J] X Ò ¦ o\ ¦ s 6
x H í ¦5 Å q q + þ A ç ß [ O > (Ultrafast Nonlinear Inter- ferometer: UNI) ~ ½ ÓZ O [1]õ SOA | 9 & h ) a s Ö 0 q H ç ß [ O
> (Michelson Interferometer) ~ ½ ÓZ O [2], Õ ªo ¦ SOA _
s 1 p q í oü < © ¨ 8 : £ ¤$ í ` ¦ 1 l x r \ s 6 x H XGM (cross gain modulation) ~ ½ ÓZ O [3,4]Ü ¼ Ð ½ ¨ & ³÷ &# Q M ® o .
s
× æ XGM ~ ½ ÓZ O ` ¦ s 6 x H F g OR 7 H o è H ¸
ñ (probe signal)ü < * 3 á Ô ñ (pump signal) ¿ º > h _
SOA\ ¦ : x õ > ) a . s M : SOA ? /\ " f s 1 p q í o r
ç ß \ q K s 1 p q r4 ¤ r ç ß (gain recovery time)s Ö ¼o l
M :ë H \ ` O Û ¼ ñ_ ; ¤ s 7 £ x # 1 l x 5 Å q ¸ 2.5 Gbps s Ð ] jô Ç ) a . ¢ ¸ô Ç 2> h_ SOA\ ¦ s 6 x l M :
∗
E-mail: [email protected]
ë
H \ F g OR 7 H o è _ ½ ¨ ¸ B Ä º 4 ¤ ¸ ú ô Ç é ß & h ` ¦
° ú
¦ e [3,4].
: r 7 Hë H É r 0 A\ " f [ O " î ) a ¿ º > h_ é ß & h ` ¦ K l 0 A K
" f é ß { 9 SOA_ s 1 p q í o : £ ¤$ í ` ¦ s 6 x ô Ç F g OR 7 H o
è _ 1 l x : £ ¤$ í s 10 Gbps\ " f ¸_ z ´+ « >Ü ¼ ÐÂ Ò' % 3
É
r õ \ ¦ % 6 £ § Ü ¼ Ð ] jr ô Ç . : £ ¤ y , ¸_ z ´+ « >\ " f F g OR 7 H o è H $ ½ ©g Ë :& h ` O Û ¼ ñJ ` ¦ ¸
ñü < * 3 á Ô ñ Ð s 6 x < ÊÜ ¼ Ð+ $ í / B N& h F g OR 7 H o 1
l
x s % 3 # Q& . Õ ªo ¦ e _ _ Ô ¦ ½ ©g Ë :& h ` O Û ¼ ñ J
s ¸ ñü < * 3 á Ô ñ Ð s 6 x| ¨ c M : ¸ F g OR 7 H o
è _ : £ ¤$ í s % 3 # Q& .
II. ¹ Å° Ë Ñ OR À X ØP } º 8 ý Ò ÞX c l Ì ¦ RP
: r 7 Hë H \ " f H SOA _ XGM (cross gain modulation) :
£ ¤$ í ` ¦ ° ú H inverter _ " é ¶ o 6 £ x6 x ÷ &% 3 [5]. Fig. 1 É r
¸¿ º ` O Û ¼ + þ AI ¸ ñü < * 3 á Ô ñ SOA\ { 9
| ¨
c M : Ò q tl H s 1 p q í o : £ ¤$ í ` ¦ Ð# ï r . : r 7 Hë H É r F g
7 H o è _ 1 l x 5 Å q ¸\ ¦ ¾ Ó © r v l 0 AK " f Fig. 1(a)ü <
° ú
s ¸ ñü < * 3 á Ô ñ ¸¿ º RZ (return to zero) J
Ü ¼ Ð ë ß [ þ t # Q . Z } É r F g [ jl \ ¦ ° ú H * 3 á Ô ñ
SOA \ { 9 ÷ & SOA ? /Â Ò\ " f î r ì ø Í ¦° ú (carrier de- pletion) & ³ © s { 9 # Qè ß . " f { 9 & ñ ô Ç Å Òl _ ` O Û ¼+ þ A I
¸ ñ SOA? /\ î r ì ø Í ¦° ú Ð Ò q t| s 1 p q
¸ (gain modulation)ü < 1 l x{ 9 > ¸÷ &# Q Ø ¦§ 4 ÷ &Ù ¼ Ð Ø
¦§ 4 ñ H { 9 § 4 * 3 á Ô ñü < ì ø Í@ / 7 H o \ ¦ ° ú H . SOA _
Inverter Ð" f_ : £ ¤$ í É r Fig. 1(a) \ ¸ ú ¬ ¹ ÷ &# Q e
. " f Fig. 1(b)ü < ° ú s ` O Û ¼+ þ AI _ ¸ ñü < * 3
-338-
½ ¨ 7 Hë H é ß { 9 ì ø Í ¸^ F g7 £ x; ¤ l \ ¦ s 6 x ô Ç D h Ðî r F g OR 7 H o > s à Ô_ ¸_ z ´+ « > – % ò I · ^ ñ -339-
Fig. 1. (a) Operation principle of XGM and (b) gen- eration of a converted signal by use of the XGM in a semiconductor amplifier.
á
Ô ñ SOA\ ì ø Í@ / ~ ½ Ó ¾ ÓÜ ¼ Ð { 9 | ¨ c M : ¨ 8 ) a ñ (converted signal) H * 3 á Ô ñ \ O ` ¦ M :ë ß Ø ¦§ 4 ) a .
Fig. 2 H F g OR 7 H o è \ ¦ ½ ¨ & ³ l 0 Aô Ç > h¥ Æ ¸ ü
< OR o ³ ðs . Fig. 2\ " f ` O Û ¼ e ` ¦ M : “ON”
© I s ¦ ` O Û ¼ \ O ` ¦ M : “OFF” © I Ð & ñ _ , Fig.
1 \ " f [ O " î ) a XGM _ 1 l x " é ¶ o \ _ K * 3 á Ô ñ (B)
“OFF” © I { 9 M : ¸ ñ (A) H SOA\ ¦ : x õ # Ø ¦§ 4
ñ “ON” © I Ð ) a . " f Fig. 2(a) % ! 3 A J
ñ (1100)ü < B J ñ (0110) y y ì ø Í@ /~ ½ Ó ¾ ÓÜ ¼ Ð SOA \ Å Ò{ 9 ÷ & , Aü < B ñ_ Boolean AB (1000)
Ø
¦§ 4 ) a . Õ ªo ¦ Ø ¦§ 4 ) a ñ B ñü < ½ + Ë5 gf Ü ¼ Ð +
Aü < B ñ_ F g OR 7 H o ° ú כ Boolean AB + B
% 3 # Q . Boolean AB + B H Fig. 2(b) \ e H F g OR 7 H o è _ o ³ ð (truth table)ü < { 9 u Ù ¼ Ð F g OR 7 H o è é ß { 9 SOA\ ¦ s 6 x # ½ ¨ & ³| ¨ c à º e .
III. { ¢8 ý ÷ m Ç] M ö õ m Í À X Ø8 ý
Fig. 2(a) \ " f [ O " î ) a F g OR 7 H o è _ s n # Q
\
¦ 7 £ x l 0 AK " f VPIphotonics
T M_ VPI r Ó ý t Y Us '
[6]\ ¦ s 6 x # ¸_ z ´+ « >s à º' ÷ &% 3 . VPI r Ó ý t Y U
Fig. 2. (a) Schematic diagram of the OR gate using the XGM in the SOA and (b) truth table of the all-optical OR gate.
s
' Ð ¸_ z ´+ « >` ¦ ½ + É M : F g OR 7 H o è H 1 l x 5 Å q ¸
\
¦ ¾ Ó © r v l 0 A # ¸ ñ Aü < * 3 á Ô ñ B ¸
¿
º 10 Gbps RZ J _ ñ\ ¦ ° ú ¸2 ¤ F g` O Û ¼ µ 1 ÏÒ q tl
s
6 x ÷ &% 3 . Õ ªo ¦ { 9 § 4 ñ J Aü < B\ ¦ Ò q t$ í l 0
Aô Ç F g ¸l , Ø ¦§ 4 ñ F g` ¦ ì r o < Ê É r ½ + Ë l 0 A ô
Ç 1 × 2 F gì r C l , SOA ? /\ " f î r ì ø Í ¦° ú (carrier depletion) & ³ © ` ¦ Ä » ¸ l 0 Aô Ç F g t l , { 9 § 4 ñ J
(B)` ¦ * 3 á Ô ñ Ð 7 £ x; ¤ l 0 Aô Ç # Q· ¢ §' F g$ 3 Ä » 7 £ x
;
¤ l (EDFA), Õ ªo ¦ * 3 á Ô ñü < ¸ ñ ì ø Í@ /~ ½ Ó ¾ Ó Ü
¼ Ð { 9 ÷ & H SOA 1 p x Ü ¼ Ð ¸_ z ´+ « > © u ½ ¨$ í ÷ &% 3
. Fig. 3 É r VIP r Ó ý t Y Us ' \ ¦ s 6 x # ¸_ z ´+ « >\ ¦ l
0 Aô Ç F g OR 7 H o è _ ½ ¨$ í ¸s . $ ñ Aü <
ñ B y y Ò q t$ í ) a Ê ê ñ A H SOA _ ý a8 £ ¤ \ " f { 9
§ 4
) a . Õ ªo ¦ ñ B H 1 × 2 F gì r C l \ " f ì r o ) a Ê ê, ô
Ç ñ H SOA _ Ä º8 £ ¤ \ " f { 9 § 4 ÷ & ¦ É r ñ H 1 × 2 F g ½ + Ël \ " f SOA_ Ø ¦§ 4 ñ Boolean ABü < ½ + Ë
÷
&# Q Boolean AB + B % 3 # Q . " f F g OR 7 H o
è _ 1 l x : £ ¤$ í s ¸_ z ´+ « >_ õ ÐÂ Ò' % 3 # Qt >
) a .
Fig. 4 H * 3 á Ô ñü < ¸ ñ_ J s ¸¿ º ½ ©g Ë :& h
ñJ (regular signal pattern){ 9 M : VPI r Ó ý t Y Us '
Ð ¸_ z ´+ « >` ¦ ô Ç F g OR 7 H o è _ 1 l x : £ ¤$ í s .
` O
Û ¼ ñ e ` ¦ M :ü < \ O ` ¦ M :\ ¦ y y 1õ 0Ü ¼ Ð
½
¨ì r , ¸ ñ A H 11001100... _ ` O Û ¼ \ P (pulse
train)[Fig. 4(a)] s ¦ * 3 á Ô ñ B H 01100110... _ ` O Û ¼
-340- ô Dz D GÓ ü t o < Æ rt “D hÓ ü t o ”, Volume 57, Number 5, 2008¸ 11 Z 4
Fig. 3. Experimental setup of a VPI simulator in order to obtain the logical operation of the all-optical OR gate.
Fig. 4. Simulation results of the OR gate using regular signal patterns as probe and pump signals: (a) probe signal A(1100), (b) pump signal B(0110), (c) Boolean AB (1000), and (d) Boolean AB + B as logic OR.
\ P
[Fig. 4(b)]s . ñ Aü < B y y SOA_ ý aÄ º8 £ ¤
\
" f { 9 | ¨ c M : * 3 á Ô ñ_ ` O Û ¼\ _ K SOA_ s 1 p q
í o Ò q tl ¸2 ¤ * 3 á Ô ñ_ F g [ jl ¸] X ÷ & , ¸
ñ_ ` O Û ¼ H * 3 á Ô ñ_ ` O Û ¼ \ O ` ¦ M :ë ß Ø ¦§ 4 ÷ &Ù ¼
Ð SOA_ Ø ¦§ 4 ñ H Boolean AB 10001000..._ ` O Û
¼ \ P [Fig. 4(c)]s ) a . s ñ F g ½ + Ël \ _ K
ñ Bü < ½ + Ë5 gt Boolean AB + B 11101110..._ ` O Û ¼
\ P
[Fig. 4(d)]s % 3 # Qt Ù ¼ Ð F g OR 7 H o è ) a .
Fig. 5 H * 3 á Ô ñ Aü < ¸ ñ B ¸¿ º Ô ¦ ½ ©g Ë :& h
ñJ (random signal pattern){ 9 M : ¸_ z ´+ « >` ¦ ô Ç F
g OR 7 H o è _ 1 l x : £ ¤$ í s . e _ J _ ` O Û ¼ \ P
Ð ë ß [ þ t # Qt H ñ Aü < B_ ` O Û ¼\ P É r y y Fig. 5(a)ü <
Fig. 5(b) \ " f Ð# . Fig. 5(c)\ " f ` O Û ¼\ P É r ñ B _
` O Û ¼ \ O H 0 Au \ ñ A_ ` O Û ¼ e ` ¦ M :ë ß
Fig. 5. Simulation results of the OR gate using random signal patterns as probe and pump signals: (a) probe signal A (1100), (b) pump signal B(0110), (c) Boolean AB (1000), and (d) Boolean AB + B as logic OR.
Ù ¼ Ð Boolean AB ) a . Õ ªo ¦ Boolean AB
ñ Bü < F g ½ + Ël \ " f ½ + Ë5 g Boolean AB + B Fig.
5(d) \ e . " f 10 Gbps\ " f e _ J _ ` O Û ¼\ P Ð µ
1 ÏÒ q t ) a * 3 á Ô ñü < ¸ ñ x 9 é ß ô Ç > h_ SOA\ ¦ s 6 x
# F g OR 7 H o è _ 1 l x : £ ¤$ í s % 3 # Q H z ´ s
% 6 £ § Ü ¼ Ð ¸_ z ´+ « >Ü ¼ ÐÂ Ò' { 9 7 £ x ÷ &% 3 .
IV. + s Ç Â ] Ø
: r 7 Hë H \ " f % 6 £ § Ü ¼ Ð ô Ç > h_ ì ø Í ¸^ F g7 £ x; ¤ l (SOA) ë
ß ` ¦ s 6 x ô Ç D h Ðî r F g OR 7 H o è ] jî ß ÷ & ¦ VIP r
Ó ý t Y Us ' \ ¦ s 6 x ô Ç ¸_ z ´+ « >Ü ¼ ÐÂ Ò' F g OR 7 H o 1
l
x s { 9 7 £ x ÷ &% 3 . s OR 7 H o è H l > r \ µ 1 ϳ ð ) a OR 7 H o è [3,4]\ q K ½ ¨ ¸ é ß í H ¦, é ß { 9 SOA\ ¦ s
6 x l M :ë H \ â ] j& h s ¦, 1 l x 5 Å q ¸ H 10 Gbit/s s Ù
¼ Ð ¦5 Å q1 l x ` ¦ H © & h ` ¦ ° ú ¦ e .
F g OR 7 H o è H É r F g 7 H o è [ þ t (AND, OR, XOR, NOR, NAND) õ < Êa F g( É Óh As F g
ñ% o r Û ¼% 7 ` ¦ ½ ¨$ í ½ + É M : N S Z ~` ¦ Ã º \ O H Ù þ d & h è
s . " f F g OR 7 H o è H F g á Ô Ð[ j" fü < ° ú
É
r è x 9 Â Ò¾ ¡ § 1 p x _ l 0 p x ¾ Ó © ` ¦ 4 R` ¦ ÷ r ë ß m ,
F g r Ð x 9 F g r Û ¼% 7 ½ ¨ & ³\ × æ כ ¹ô Ç % i ½ + É` ¦ ½ + É כ Ü ¼
Ð l @ / ) a .
½ ¨ 7 Hë H é ß { 9 ì ø Í ¸^ F g7 £ x; ¤ l \ ¦ s 6 x ô Ç D h Ðî r F g OR 7 H o > s à Ô_ ¸_ z ´+ « > – % ò I · ^ ñ -341-
Y
c p w à U Ø ô
[1] N. S. Patel, K. L. Hall and K. A. Rauschenbach, Opt.
Lett. 21, 1466 (1996).
[2] T. Fjelde, D. Wolfson, A. Kloch, C. Janz, A. Co- quelin, I.19-4 Guillemot, F. Gaborit, F. Poingt, B.
Dagens and M. Ren, Electron. Lett. 36, 813 (2000).
[3] Young Tae Byun, Jae Hun Kim, Young Min Jhon, Seok Lee, Deok Ha Woo and Sun Ho Kim, Hankook Kwanghak Hoeji 13, 151(2002).
[4] Young Tae Byun, Young Min Jhon, Jae Hun Kim, Seok Lee, Deok Ha Woo, Sun Ho Kim, Kwang Nam Kim, Patent No. (US 6, 804, 047 B2), 2004.
[5] Jae Hun Kim, Young Min Jhon, Young Tae Byun, Seok Lee, Deok Ha Woo and Sun Ho Kim, IEEE Pho- tonics Technol. Lett. 14, 1436 (2002).
[6] Jae Hun Kim, Chang Wan Son, Young Il Kim, Young Tae Byun, Young Min Jhon, Seok Lee, Deok Ha Woo, Sun Ho Kim and Young Wan Choi, in Proceedings of the 3rd International Conference on Numerical Simulation of Semiconductor Optoelectronic Devices (Tokyo, 2003), p. WP9.
Simulation of a Novel All-optical OR Gate by Using a Single Semiconductor Optical Amplifier
Young Tae Byun
∗and Sun Ho Kim
Intelligent System Research Division, Korea Institute of Science and Technolog, Seoul 136-791 (Received 26 September 2008)
By using gain saturation of a semiconductor amplifier (SOA), we propose a novel all-optical OR logic gate using a single SOA, and we successfully demonstrate that gate by using a VPI simulator.
Tor the first time the operation characteristics of the all-optical OR logic gate were simulated at 10 Gbps by using regular and random signal patterns as probe and pump signals.
PACS numbers: 42.25.Bs
Keywords: All-optical OR logic gate, Semiconductor optical amplifier (SOA), Cross-gain modulation (XGM)
∗
