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Temporal Cloaking Through Kerr Nonlinearity and Doppler Broadening

Thesis Info

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Author

Jabar, Mian Syed Abdul

Program

PhD

Institute

University of Malakand

City

Malakand

Province

KPK

Country

Pakistan

Thesis Completing Year

2018

Thesis Completion Status

Completed

Subject

Physics

Language

English

Link

http://prr.hec.gov.pk/jspui/bitstream/123456789/9942/1/Mian_Syed_Abdul_Jabar_Physics_2018_UoM_Malakand_Main%20part.pdf

Added

2021-02-17 19:49:13

Modified

2024-03-24 20:25:49

ARI ID

1676727563784

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The newborn phenomenon of temporal cloaking is investigated under the e®ects of Doppler broadening and Kerr nonlinearity in di®erent atomic me- dia. The optical properties of these media are manipulated in such a manner that a time gap is created in the propagating probe light where events or information can be transmitted undetected. To create the cloaking time gap, the enhanced subluminal and superluminal behaviors of the probe ¯eld are focused. The opened temporal gap is closed by an inverse process that involves reverse modi¯cation of the optical properties of the medium. Ini- tially, we consider a ¯ve-level M-type atomic con¯guration of rubidium. The concept of Doppler broadening is introduced along with the superposition of the double resonant ¯elds in the system. Phase shift variations are caused in the medium which result into a signi¯cant delay and advancement of the probe pulse. The delay and advancement times lead to the generation of a time hole for concealing information in the temporal domain. A microsecond time gap is attained without signi¯cant distortion in the pulse shape. The time gap is further increased to several orders of microseconds with increase in the Doppler width. Next, we investigate propagation of the light pulse in a four-level Doppler broadened sodium atomic system. The possibility of creating a temporal gap is discussed on the basis of spectral hole burning in the system. The probe pulse is observed to delay in the hole burning region while it advances in the nearest neighboring region. A cloaking time gap of the order of microseconds is achieved in the slow and fast light regime. The time gap is modi¯ed with the inverse Doppler e®ect. The time gap can also be tuned and modi¯ed with the strengths of the coupling ¯elds, if the Doppler width is kept constant in the system. Finally, we extend our studies to the three-level rubidium atomic system. The pulse delay and advancement vi times are observed at speci¯c system parameters in the presence of self-Kerr ¯eld e®ect. The delay and advance times are enhanced with increase in the intensity of self-Kerr ¯eld. A cloaking time gap of the order of nanosecond is created in the observed fast and slow light. Increase of the time gap is observed with increase in the intensity of self-Kerr nonlinearity. The time gap is enhanced to several orders of nanosecond, su±cient to hide any prac- tical event. The time gaps are closed by reverse manipulation of the optical properties. Our results may contribute to strengthening the idea of hiding events in successive temporal gaps for achieving enhanced security of the communication systems.
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خطۂ سیالکوٹ میں اردو شاعری کی روایت

سیالکوٹ ایک تاریخی اور ادبی خطہ  رہا ہے۔ اس کی تاریخ پانچ ہزار سال پر محیط ہے۔یہ خطہ  جغرافیائی لحاظ سے اس مقام پر واقع ہے جہاں کئی آبی گذرگاہیں ہیں۔ کشمیر اور پنجاب کے دیگر تجارتی شہروں سے اس کا قریبی رابطہ ہے۔ سیالکوٹ تاریخی، ثقافتی، سماجی، تہذیبی، علمی اور ادبی لحاظ سے لاہور اور دوسرے ادبی، ثقافتی، تہذیبی، تاریخی اور علمی شہروں سے کسی طور پر بھی کم نہیں۔ اس شہر کی ثقافت توانائی اور رنگا رنگی لیے ہوئے ہے۔ یہاں کے میلے ٹھیلے، روایتی تہوار اور دیگر ثقافتی سرگرمیاں اس  خطے  کو  ہمیشہ ممتاز کرتی رہی ہیں۔ 

سیالکوٹ کو اقبال و فیض کے مولد ہونے کا  لا زوال فخر حاصل ہے۔  یہ ایک صنعتی شہر ہے ۔اس کی آبادی  تقریباً تیس  لاکھ سے  زیادہ نفوس پر مشتمل ہے سر زمین  سیالکوٹ صدیوں  کی انسانی تہذیب و تمدن اور ادب و ثقافت کا عظیم الشان گہوارہ ہے۔ اس دھرتی کے تاریخی آثار  مدت سے مورخین و ماہرین آثار قدیمہ کی دلچسپی کا سامان بھی رہے ہیں۔ یہاں کی تہذیب ٹیکسلا اور موہنجو ڈارو کی تہذیبوں کے ہم پلہ ہے۔

   سیالکوٹ  کی مٹی بڑی زرخیز اور مردم خیز ہے۔سرزمین سیالکوٹ نے علم و ادب اور فنون لطیفہ  کے  میدانوں میں گراں قدر خدمات سرانجام دی ہیں۔ اس خطے کے باشندوں  نے پاکستان کی صنعتی  و اقتصادی ترقی کے ساتھ ساتھ علم و فن کی خدمت بھی جاری رکھی۔ ماضی میں ملا کمال کشمیری، ملا عبدالحکیم  سیالکوٹی،  امین حزیں سیالکوٹی، اثر صہبائی، مرزا ریاض  اور غلام الثقلین نقوی نے علمی وادبی  حوالے سے سیالکوٹ کا نام روشن کیا۔ مولوی میر حسن، مولوی ابراہیم  میر، ڈاکٹر جمشید راٹھور اور یوسف سلیم چشتی نے علم کی پیاس بجھائی۔ڈاکٹر  وحیدقریشی سیالکوٹ کے ادبی ماحول کے بارے میں رقمطراز ہیں۔

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Colonialism is strictly referred to the policies and Methods by an Imperial Power maintained and extended its control over the territories or People. A policy of extending a Country’s Power and influence through diplomacy or military. It also affects the literature of the Subject Country which is controlled by the colonialist. This Article Present an analysis of Colonial system and its impact for migration and its hurdles in Urdu Poem.

Production Potential and Postharvest Management of Cut Rose Flowers in Punjab Pakistan

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