Question

الشكل التخطيطي يوضح انتقالات ذرتي الهيليوم والنيون بين مستويات الطاقة أثناء عملية إنتاج الليزر.

أي انتقالين يحدثان عند اصطدام ذرة هيليوم منارة بذرة نيون غير منارة؟

• A. الانتقالان 4.1
• B. الانتقالان 4.3
• C. الانتقالان 3.5
• D. الانتقالان 2.5

Answer 1

Answer: (D)

4

Answer 2

The process of laser production in a Helium-Neon laser involves the following key steps related to the collision:

1. An excited Helium atom (at energy level E2) collides with an unexcited Neon atom (at energy level E0).

2. During this collision, the Helium atom transfers its energy to the Neon atom.

   • The Helium atom de-excites from E2 to E1. This transition is represented by Transition 5 in the diagram for Helium.
   • The Neon atom gets excited from E0 to E2'. This upward transition is not numbered in the diagram.

3. Once the Neon atom is in the excited state E2' (the upper laser level), it undergoes stimulated emission, transitioning to a lower energy level E1' (the lower laser level), and emitting a laser photon. This is the main laser transition and is represented by Transition 2 in the diagram for Neon.

Therefore, the two transitions that occur as a direct result of the collision and the subsequent laser action are the de-excitation of Helium (Transition 5) and the laser transition in Neon (Transition 2).

The correct option is 4, which states "الانتقالان 2.5" (Transitions 2,5).

When an excited Helium atom (He*) at E2 collides with a ground state Neon atom (Ne) at E0, the Helium atom de-excites to its ground state E1 (Transition 5), transferring its energy to the Neon atom, which then gets excited to E2'. From this excited state E2', the Neon atom undergoes stimulated emission (laser action) to E1' (Transition 2).