There is always a bull market somewhere.

Despite shifting headlines and constantly evolving market narratives, certain stocks and sectors continue to benefit from prevailing economic regimes. In the current environment, traditional leaders such as the Magnificent Seven have softened amid concerns around excessive AI capex, while geopolitical tensions in the Middle East remain unresolved adding further uncertainty. Yet, even against this backdrop, major indices sit just a few percentage points below record highs, and a wide range of investment themes continue to push higher.

Against this landscape, I screened the Zacks Rank #1 list for risk-adjusted momentum. The three stocks that stand out are Ciena ((CIEN Quick QuoteCIEN - Free Report) ), Century Aluminum ((CENX Quick QuoteCENX - Free Report) ) and Micron Technology ((MU Quick QuoteMU - Free Report) ). Each is being driven by a combination of improving fundamentals, reflected in earnings revisions and growth expectations, and powerful macro tailwinds, including tariffs and the ongoing AI infrastructure buildout.

Image Source: Zacks Investment Research

Century Aluminum (CENX Quick QuoteCENX - Free Report) : Tariffs Propel the Stock Higher

Century Aluminums’ strength is a relatively straightforward tariff-driven story, layered on top of meaningful operational progress. As the largest domestic producer of primary aluminum, Century is uniquely positioned to benefit from current trade dynamics. The company sells into the US market at tariff-inflated prices while avoiding the cost burden those tariffs impose on imported supply, creating a powerful pricing advantage.

Importantly, the policy backdrop remains firmly intact. The Supreme Court’s February ruling on IEEPA did not impact Section 232 steel and aluminum tariffs, which remain fully in force. That clarity has helped reinforce investor confidence that the current pricing environment can persist, at least in the near to intermediate term.

This favorable setup is clearly reflected in the fundamentals. Century carries a Zacks Rank #1 (Strong Buy), with earnings estimates surging 42% for this year and 64% for next year. Furthermore, sales are projected to climb nearly 30% this year and another 15% next year.

Despite the run, valuation remains reasonable on the surface. Shares trade at approximately 8.3x forward earnings, well below the company’s 10-year median of 15.4x. That said, multiples in commodity businesses can be misleading, as they often compress near peak earnings periods. Even so, the combination of strong revisions, supportive policy, and improving operations continues to attract capital.

Technically, the stock is confirming that strength. CENX is trading just below multi-year highs, with sustained momentum suggesting investors are increasingly positioning around this tariff-driven theme, which could be persistent.

Image Source: Zacks Investment Research

Ciena (CIEN Quick QuoteCIEN - Free Report) : Optics Stocks Lead the AI Themes

As the AI infrastructure buildout has progressed, leadership has steadily moved down the stack from broad, foundational players like Nvidia and its GPUs to more specialized, downstream beneficiaries such as ventilation providers and optical networking companies like Ciena. As compute power scales exponentially, the ability to move data quickly and efficiently has become just as critical as generating it. Optical networking sits at the center of that shift, enabling the high-speed, low-latency data transmission required to support increasingly dense and distributed AI workloads.

This evolving role in the AI ecosystem has driven powerful gains across the optical networking space, supported by meaningful upgrades to earnings expectations. Ciena carries a Zacks Rank #1 (Strong Buy), underpinned by broad-based upward revisions to profit estimates across all timeframes.

The stock has more than doubled over the past six months, pushing valuation to elevated levels at roughly 60.6x forward earnings. By most measures, that is a demanding multiple. However, earnings are projected to grow at an annual rate of 53% over the next three to five years, which helps contextualize the premium investors are willing to pay.

Momentum remains firmly intact, with shares continuing to push to new all-time highs today. While buying stocks at these levels can understandably give some investors pause, sustained breakouts are often a hallmark of strong underlying demand. In these environments, the trend can persist longer than expected, though disciplined risk management remains essential.

Image Source: Zacks Investment Research

Micron Technology (MU Quick QuoteMU - Free Report) : Memory Stocks Continue to Gain

Micron Technology has been one of the market’s standout performers since last spring. Like many leaders in this cycle, it is a direct beneficiary of the AI infrastructure buildout, but in this case, the driver is memory. More specifically, a structural shortage in high-bandwidth memory (HBM), a critical component for AI workloads, has pushed Micron to the center of the investment theme.

As AI models grow more complex and data-intensive, demand for HBM has surged well ahead of supply. Micron, as one of the key producers of this specialized memory, is uniquely positioned to capitalize on that imbalance. The result has been a powerful combination of pricing strength, improving margins, and rapidly rising earnings expectations.

Technically, the stock continues to confirm that strength. MU has developed a consistent pattern of consolidation followed by breakout, and that dynamic remains intact. Over the past week, shares broke out once again from a clear base to new highs, reinforcing its position as a leading momentum name. This type of price action, particularly in a supply-constrained environment, tends to attract incremental capital as investors position around the trend.

Fundamentals are equally compelling. Micron carries a Zacks Rank #1 (Strong Buy), supported by unanimous upward revisions to estimates. Sales are expected to grow 109% this year and 36% next year, while earnings are projected to surge 334% this year and another 50% next year. Despite that growth, the stock trades at just 12.3x forward earnings.

That multiple, however, must be viewed in the proper context. Memory remains a deeply cyclical, commodity-like business, and peak earnings periods often coincide with compressed valuation multiples. Even so, the current setup, driven by a structural AI-related shortage rather than a typical cycle, suggests the strength may prove more durable than in past upcycles. For investors taking a portfolio-based approach, this remains a higher-beta, momentum-driven opportunity with both significant upside potential and inherent cyclical risk.

Image Source: TradingView

Should Investors Buy Shares in MU, CIEN and CENX?

Momentum strategies are not without risk, but they remain one of the most effective ways to align with where capital is actively flowing. What stands out about MU, CIEN, and CENX is not just their price strength, but the diversity of the underlying drivers, including AI infrastructure demand, optical networking bottlenecks, and tariff-driven pricing. This type of uncorrelated leadership is often a sign of a healthy, broadening market rather than a narrow, fragile rally.

That said, momentum requires discipline. These stocks are working because fundamentals and revisions are moving in the right direction, but price alone cannot be the thesis. A structured approach, diversified across themes, utilizing strict risk management, and a willingness to cut losers is essential when operating in momentum names.

There is also a behavioral component worth acknowledging. Many of the market’s biggest long-term winners spent extended periods making new highs, often appearing “too expensive” along the way. Strong trends tend to persist longer than expected, particularly when supported by real earnings power and macro tailwinds.

For investors willing to embrace that framework, names like MU, CIEN, and CENX represent where momentum and fundamentals are currently aligned.